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At least 109 records · Page 6Linked to original sources

PubMed1992

Leishmania major: differential regulation of the surface metalloprotease in amastigote and promastigote stages.

During its life cycle, the protozoan parasite Leishmania major alternates from an intracellular amastigote form in the mammalian host to a flagellated promastigote form in the insect vector. The expression of the surface metalloprotease (PSP) during differentiation in vitro was investigated by Western and Northern blots, by immunoprecipitation of cells metabolically labeled with [35S]methionine or labeled at the surface with radioactive iodine, and by quantification of the proteolytic activity in substrate-containing polyacrylamide gels. We report that the surface metalloprotease is down-regulated at both the mRNA and the protein level in amastigotes, where it represents less than 1% of the equivalent proteolytic activity detected in promastigotes. A significant amount of mRNA is detected 4 hr after the onset of differentiation. The expression of the protease begins at that time and reaches steady state 8 hr later. The synthesis of PSP precedes the complete morphological differentiation to the promastigote stage and the appearance of the lipophosphoglycan, another major promastigote surface component. In contrast to PSP, a family of mercaptoethanol-activated proteases present in the amastigote exists only at a reduced level in the promastigote. The confinement of the surface metalloprotease to the insect stage of the parasite suggests that it has no physiological function in the parasitism maintenance of mammalian host macrophages.

Animals↗

PubMed1988

Lactate dehydrogenase isoenzymes are present in matrix vesicles.

Matrix vesicles were isolated from epiphyseal growth plates of young rabbits. Lactate dehydrogenase activity was detected in the isolated matrix vesicles only in the presence of detergents, suggesting that NADH, the cofactor for the assay, does not penetrate the membrane of matrix vesicles. In contrast, the activity of alkaline phosphatase, a marker enzyme of the outer surface of matrix vesicles, was detected in the matrix vesicles using p-nitrophenyl phosphate as the substrate both in the presence and absence of detergents. Lactate dehydrogenase activity was detected only in the cytosol of chondrocytes of the epiphyseal growth plates but not in other subcellular fractions, showing that lactate dehydrogenase is not from the plasma membrane and membranes of intracellular organelles of chondrocytes. The isolated matrix vesicles contained all five lactate dehydrogenase isoenzymes but did not possess other cytosolic enzymes. These results show that lactate dehydrogenase is located in the matrix vesicles and suggest the presence of a mechanism for the specific uptake of cytosolic lactate dehydrogenase and the possibility of enzymatic quantification of the matrix vesicles at various calcification sites.

Animals↗

PubMed1988

A chimeric mitochondrial precursor protein with internal disulfide bridges blocks import of authentic precursors into mitochondria and allows quantitation of import sites.

Bovine pancreatic trypsin inhibitor (which contains three intramolecular disulfide bridges) was chemically coupled to the COOH terminus of a purified artificial mitochondrial precursor protein. When the resulting chimeric precursor was presented to energized isolated yeast mitochondria, its trypsin inhibitor moiety prevented the protein from completely entering the organelle; the protein remained stuck across both mitochondrial membranes, with its NH2 terminus in the matrix and its trypsin inhibitor moiety still exposed on the mitochondrial surface. The incompletely imported protein appeared to "jam" mitochondrial protein import sites since it blocked import of three authentic mitochondrial precursor proteins; it did not collapse the potential across the mitochondrial inner membrane. Quantification of the inhibition indicated that each isolated mitochondrial particle contains between 10(2) and 10(3) protein import sites.

Alcohol Dehydrogenase↗

PubMed2025

MLL1 downregulation drives hair cell ferroptosis via mitochondrial and endoplasmic reticulum stress mechanisms through PERK-eIF2α-ATF4-Chop and PI3K/Akt-Lrp1 signaling pathway.

BACKGROUND: Sensorineural hearing loss is characterized by irreversible hair cell (HC) degeneration. Ferroptosis, which is marked by the accumulation of reactive oxygen species and elevated levels of lipid peroxidation products, has been shown to contribute to drug-mediated auditory impairment. This study aimed to elucidate the role of mixed-lineage leukemia 1 (MLL1) in HC survival in the auditory system. METHODS: The HEI-OC1 auditory cell line and postnatal cochlear explants were evaluated using MM-102, a specific MLL1 histone methyltransferase inhibitor. Western blotting, quantitative polymerase chain reaction, electron microscopy, and immunofluorescence were used to elucidate the role of MLL1 in regulating ferroptosis in HC injury. RNA sequencing (RNA-seq) was used to analyze the molecular mechanisms of MLL1 intervention in HC injury from an epigenetic perspective. RESULTS: Our findings demonstrated that immunofluorescence staining revealed a crucial role of MM-102 in promoting intracellular accumulation of lipid peroxides and ferrous ions. Subsequent analysis showed MLL1 downregulation-induced mitochondrial dysfunction and endoplasmic reticulum (ER) stress, with transmission electron microscopy imaging confirming ultrastructural alterations in mitochondria and ER. Mechanistic investigations identified the PERK-eIF2α-ATF4-Chop signaling axis as the regulatory pathway, evidenced by Western blotting quantification of phosphorylated PERK (p-PERK), ATF4, and Chop levels. RNA-seq analysis revealed 741 differentially expressed genes (335 upregulated and 406 downregulated). Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis specifically highlighted significant enrichment of the PI3K/Akt-Lrp1 pathway, with corresponding activation patterns of phospho (p)-Akt and Lrp1 confirmed through Western blotting analysis. CONCLUSIONS: MLL1 downregulation initiates ferroptosis in cochlear HCs. This process is intrinsically associated with the activation of mitochondrial dysfunction and ER stress. The study highlights the importance of MLL1 in HC survival, suggesting its potential as a therapeutic target for treating hearing loss.

Endoplasmic Reticulum Stress↗

PubMed1985

Quantitative 31P nuclear magnetic resonance analysis of metabolite concentrations in Langendorff-perfused rabbit hearts.

The quantitative analysis of the mobile high-energy phosphorus metabolites in isovolumic Langendorff-perfused rabbit hearts has been performed by 31P NMR utilizing rapid pulse repetition to optimize sensitivity. Absolute quantification required reference to an external standard, determination of differential magnetization saturation and resonance peak area integration by Lorentzian lineshape analysis. Traditionally accepted hemodynamic indices (LVDP, dp/dt) and biochemical indices (lactate, pyruvate) of myocardial function were measured concomitantly with all NMR determinations. Hemodynamically and biochemically competent Langendorff-perfused rabbit hearts were found to have intracellular PCr, ATP, GPC, and Pi concentrations of 14.95 +/- 0.25, 8.08 +/- 0.13, 5.20 +/- 0.58 and 2.61 +/- 0.47 mM respectively. Intracellular pH was 7.03 +/- 0.01. Cytosolic ADP concentration was derived from a creatine kinase equilibrium model and determined to be approximately 36 microM. Reduction of perfusate flow from 20 to 2.5 ml/min demonstrated statistically significant decreases in PCr, ATP, and pH as well as an increase in Pi that correlated closely with the independent hemodynamic and biochemical indices of myocardial function. The decrease in ATP and PCr concentrations precisely matched the increase in Pi during reduced flow. These results constitute the first quantitative determination of intracellular metabolite concentrations by 31P NMR in intact rabbit myocardium under physiologic and low flow conditions.

Adenosine Diphosphate↗

PubMed1991

Triggering module for waveform digitization.

A full circuit description is provided for a triggering module used to assist a small laboratory computer in digitizing muscle force- and EMG waveforms. During the stimulation of individual motor units using a standard fatigue test, a train of 13 pulses are delivered at a rate of 40 pps either intracellularly to a motor neuron, or extracellularly to functionally isolated single motor axons from among divided ventral-root nerve filaments. Trains are delivered at a rate of 1/s for the duration of the test, which may range from 120 to 3600 s. Both the force and EMG profiles undergo changes during such tests and the quantification of parameters associated with their waveforms are of interest to neurobiologists. The triggering module allows a typical small laboratory computer to capture user-selected waveforms and thereby reduces the programming problems, timing constraints, storage requirements and analysis time associated with obtaining these parameters. The versatile circuit may be easily adapted to solve similar data-acquisition problems. The method was implemented on an Apple Macintosh II computer but can also be applied to other systems equipped with appropriate software and a data-acquisition card.

Animals↗

PubMed1987

Flow cytometric quantification of cholesteryl ester-containing "foam" cells. I. Analysis of aortas from normolipidemic swine.

We have quantified using flow cytometry foam cells of aortas from normolipidemic swine varying in age from 6 months to 12 years. These swine were maintained throughout their lives on a low-fat, cholesterol-free diet. Intimal-medial tissues removed from the swine aortas were enzymatically dissociated to prepare Formalin-fixed cell suspensions. Foam cells were labeled by specific staining of their intracellular cholesteryl ester using the fluorescent dye filipin. This was carried out by first removing cellular unesterified cholesterol with ethanol, then enzymatically hydrolyzing cellular cholesteryl ester, and finally staining with filipin the unesterified cholesterol derived from hydrolysis of cholesteryl ester. Results of flow cytometric analysis indicated that thoracic foam cell densities of female swine became more variable and tended to increase with age. It appeared that there were two subgroups of female swine with either high or low levels of thoracic foam cells. A similar finding was not observed for abdominal foam cells in female swine nor for thoracic or abdominal foam cells in the smaller number of older male swine. Abdominal foam cell densities in younger males, however, also appeared to be comprised of low and high foam cell groups. Foam cell densities did not correlate with serum cholesterol or triglyceride levels. However, a genetic basis for some of the variability in foam cell densities among these animals was suggested by the observation that females with high thoracic foam cell densities had greater commonality among ancestors than did females with low thoracic foam cell densities.

Age Factors↗

PubMed1985

Quantification of DNA uptake by Dictyostelium discoideum amoebae and the stability of the DNA during growth and development.

We have developed a simple and accurate method to determine the amount of intact plasmid DNA taken up and retained by Dictyostelium discoideum amoebae during various transformation protocols. We have used this method to compare the efficiency of three different methods for introducing foreign DNA into D. discoideum amoebae. Both a calcium phosphate and a spheroplast fusion procedure gave good uptake, but no intracellular plasmid DNA was detectable after calcium chloride treatment. The exogenous DNA was rapidly lost after transformation but was 20-fold more stable during starvation rather than growth conditions, suggesting a possible approach to improving transformation efficiency. No transient expression of neomycin phosphotransferase activity of any of the heterologous animal or plant promoters used could be detected using a sensitive gel assay procedure.

DNA, Fungal↗

PubMed1976

Functional incorporation of ganglioside into intact cells: induction of choleragen responsiveness.

NCTC 2071 cells are unable to synthesize the monosialoganglioside GM1. When grown in chemically defined medium these cells contained no detectable GM1 and did not accumulate 3': 5'-cyclic AMP in response to choleragen. Incubation of the cells with [3H]GM1 permitted quantification of ganglioside uptake which was dependent on time and concentration of [3H]GM1 in the medium. Responsiveness to choleragen was demonstrated with binding of as few as 17,000 molecules of [3H]GM1 per cell; a maximal response was observed with 10(5) molecules per cell. With increasing cellular content of GM1, the rate of rise in intracellular cyclic AMP in response to choleragen was increased. With greater than 1 X 10(5) molecules of GM1 per cell, the delay between addition of choleragen and the cyclic AMP response was inversely proportional to choleragen concentration; less than 250 molecules of choleragen per cell caused a significant increase in cyclic AMP after 8 hr of incubation. Although the responsiveness of intact cells to choleragen was dependent on GM1, choleragen activation of adenylate cyclase in homogenates with 0.6 mM NAD was independent of added ganglioside. These observations are consistent with the view that exogenous ganglioside GM1 can be functionally integrated into the surface membrane of intact cells and serve as the choleragen receptor. Furthermore, although exogenous GM1 is required for choleragen responsiveness in intact cells, the ganglioside does not play an obligatory role in cell homogenates, where the surface receptor can presumably be bypassed.

Adenylyl Cyclases↗

PubMed1988

Enzyme-linked immunosorbent assay for human proapolipoprotein A-I using specific antibodies against synthetic peptide.

Apolipoprotein A-I (apoA-I), the major protein component of human high density lipoprotein, appears intracellularly as an intermediate precursor (proapoA-I) with a hexapeptide extension (Arg-His-Phe-Trp-Gln-Gln) at its amino terminus. To investigate the regulation of processes that regulate plasma apoA-I levels, a sensitive and simple assay for proapoA-I is required. We describe a specific enzyme-linked immunosorbent assay (ELISA) for quantification of proapoA-I using monospecific rabbit antibodies raised against the peptide: Arg-His-Phe-Trp-Gln-Gln-Asp-Glu-Pro. The monospecificity of antibodies to propeptide has been checked and no cross-reaction with mature apoA-I has been found although three first mature apoA-I amino acids (Asp-Glu-Pro) were included in the immunizing peptide. The assay is a non-competitive sandwich ELISA in which polystyrene microtiter plates were used with antibodies to propeptide adsorbed on the wells. After incubation with plasma samples, the bound proapoA-I was revealed by labeled rabbit polyclonal antibodies directed against mature apoA-I. The working range was 10 to 100 ng/ml, recovery of proapoA-I added to plasma was 94.6 to 106.5%, and the intra- and interassay coefficients of variation were 3.8% and 7.9%, respectively. A delipidation step using diisopropylether-n-butanol was necessary to expose antigen sites of proapoA-I in native lipoproteins. Mean level of proapoA-I in normal subjects was 87 +/- 15 micrograms/ml. It represented 7.1% of total apoA-I while in Tangier serum it represented 29%.

Apolipoprotein A-I↗

PubMed1992

Immunologic alterations in a murine model of hemorrhagic shock.

OBJECTIVE: To study multiple immune parameters in mice subjected to severe hemorrhage without fluid resuscitation. STUDY DESIGN: Controlled animal study. Anesthetized, female mice were hemorrhaged by tail bleeding. Immune parameters (spleen T-cell proliferation and activation, intracellular calcium flux, cytokine production, peritoneal neutrophil respiratory burst, and survival after intra-abdominal septic challenge) were measured at 24, 48, and 72 hrs after hemorrhage. MEASUREMENTS AND MAIN RESULTS: T-cell proliferation was decreased in animals after two 20% blood volume hemorrhages, 30 mins apart; single 30%, 40%, and 50% blood volume hemorrhages did not depress proliferation. "Helper/inducer" T cells from twice-hemorrhaged mice showed decreased expression of activation antigens (interleukin-2 receptor, Ia) after mitogen stimulation. In contrast, "suppressor/cytotoxic" T cells displayed increased activation, shown by augmented expression of interleukin-2 receptor and Ia antigens. Leukocyte production of prostaglandin E2, a mediator frequently implicated in immune down-regulation, was unaffected by hemorrhage. Secretion of tumor necrosis factor-alpha (TNF-alpha) in culture was increased when cells were harvested 48 hrs after injury. Intracellular calcium flux in stimulated lymphocytes was decreased 24 hrs after hemorrhage, suggesting deranged intracellular signal transduction. Respiratory burst activity of peritoneal neutrophils was unchanged following hemorrhage. When animals were subjected to septic challenge, the survival rate was markedly decreased after two hemorrhages (when sepsis was induced 24 hrs after hemorrhage). By 72 hrs posthemorrhage, most of the immunologic alterations, including resistance to septic challenge, had resolved. CONCLUSIONS: This uninstrumented hemorrhagic shock model allows quantification of multiple immune derangements. Immune suppression was identified after two smaller (20% blood volume) hemorrhages, but not after a single, larger hemorrhage. Immune derangements are maximal at 24 hrs posthemorrhage, and resolve in the subsequent 48 hrs.

Analysis of Variance↗

PubMed1987

Quantitative analysis of a nuclear antigen in interphase and mitotic cells.

The quantification of an interchromatin-associated antigen, designated p 105, during cellular passage through mitosis is described. Indirect immunofluorescence microscopy and immunogold electron microscopy demonstrated a qualitative increase in p 105 within the mitotic cytoplasm. Multiparameter flow cytometric analysis was performed on fixed cells sequentially stained with anti-p 105 immunofluorescence and/or propidium iodide. This analysis demonstrated approximately a tenfold increase in intracellular p 105 content as a function of progression from the G2 to the M phase. This increase was corroborated by the quantitative immunoblot analysis of colchicine-treated cell cultures and of cells sorted on the basis of anti-p 105 immunofluorescence. The data reveal that the increased levels of anti-p 105 immunofluorescence in conjunction with flow cytometry may be used effectively to quantitate mitotic index and isolate mitotic cells. The function and modulation of p 105 throughout the cell cycle is discussed.

Antigen-Antibody Complex↗

PubMed1990

DNA synthesis inhibition and reduced functional differentiation of midpregnant mouse mammary epithelia on collagen gels.

Mammary epithelial cells were examined for a link between DNA synthesis and subsequent synthesis and secretion of casein. Cells isolated from mice midway through pregnancy and cultured on collagen gels spread to form monolayers (spreading phase). Release of monolayer/gels to float in surrounding culture medium induces synthesis and secretion of casein (secretory phase). DNA synthesis was blocked during the spreading phase with cytosine arabinofuranoside (ARA C). Culture medium was assayed for casein by direct quantification of protein from SDS-PAGE fluorographs, and by immunoblotting. When induced to become secretory, cells exposed to ARA C during the spreading phase showed a marked reduction of secretion of casein as compared to control cultures (72% reduction). In contrast, cells exposed to ARA C during the secretory phase (after monolayer formation was complete) showed no significant reduction in secretion of casein. Measurement of intracellular casein in secretory phase cells showed that reduced secretion of casein by cultures blocked during the spreading phase occurs as a consequence of reduced levels of casein synthesized, and not because of an inability to secrete intracellular accumulations. The inhibitor effect was specific; there was no significant reduction in levels of total intracellular protein synthesis, and neither cell spreading nor monolayer formation was impaired by treatments. These data support the notion that DNA synthesis is a prerequisite to functional differentiation of midpregnant mouse mammary epithelia maintained on floating collagen gels.

Animals↗

PubMed1978

Intracellular electrolytes in erythrocytes during and after shock: relation to impaired consciousness.

Of 32 patients in shock and catabolic state following shock with impaired consciousness 31 exhibited raised sodium content in their erythrocytes. On the assumption that the erythrocyte membrane acts the same as nerve cell membrane, the hypofunction of erythrocyte membrane may result in impaired consciousness. The hypofunction of erythrocyte membrane is assumed by its increased permeability in shock. A positive osmotic discrepancy between measured and calculated levels denotes altered membranous permeability. Subjectively, impaired consciousness was evaluated by clinical grading. Meanwhile, as a trial of quantification of conscious levels, we applied a new technique of analysis of power spectrum obtained by computer on the autocorrelogram of the EEG during intermittent photic stimulation. This new analytic method was useful in evaluating objective changes of cerebral function. There was a good correlation between raised sodium content in erythrocytes and depressed power spectrum. The degree of increased sodium in erythrocytes seems to correlate with patients' clinical prognosis.

Adult↗

PubMed1991

Rapid determination of alpha-tocopherol in sarcoplasmic reticulum membranes by reverse phase HPLC.

A simple isocratic high performance liquid chromatograph (HPLC) system is described to perform a rapid separation, identification and quantitative determination of vitamin E (alpha-tocopherol) in biological membranes. It makes use of a reverse phase C18 column with pure methanol as the mobile phase, and an ultraviolet detector which enables its quantification in the nanogram scale. This procedure was applied to lipid extracts from whole muscle homogenate and from a preparation of sarcoplasmic reticulum vesicles from skeletal muscle, where the vitamin E contents was determined.

Animals↗

PubMed1992

Expression of CRABP-I and -II in human epidermal cells. Alteration of relative protein amounts is linked to the state of differentiation.

The physiological role of cellular retinoic acid-binding proteins (CRABPs) may be to influence the intracellular level of free retinoic acid in the cell. In the present study two isoforms of CRABP, CRABP-I and CRABP-II were partially characterized in various human Malpighian epithelia and in human cultured keratinocytes expressing various patterns of differentiation. We have developed a new sensitive radiobinding assay using a PAGE/autoradioblotting technique which effectively separates CRABP-I and CRABP-II. This method allows the simultaneous quantification of these proteins. We show that CRABP-I and -II have similar M(r) values (15,000), but differ in their dissociation constant towards retinoic acid (Kd of 16.6 nM and 50 nM respectively), in pI (4.86 and 5.13) and in their relative mobilities (RF) on PAGE under nondenaturating conditions (RF values 0.65 and 0.44). In addition, we show that CRABP-II is the major isoform expressed in human keratinocytes, in vivo as in vitro. Furthermore, we demonstrate that CRABP-II is actually the CRABP previously studied in epidermal cells by a PAGE assay (Siegenthaler & Saurat (1987) Eur. J Biochem. 166, 209-214) and whose levels are dramatically increased by retinoic acid and its analogues in human epidermis. Keratinocytes, in the absence of full terminal differentiation, as well as hyperplasia, such as cultured human differentiating keratinocytes, psoriatic plaques, and non-keratinized oral mucosa, contained high levels of CRABP-II. CRABP-I was not detected in cultured keratinocytes, whereas normal skin (at full terminal differentiation) expressed CRABP-I and CRABP-II at a ratio of approx. 1:1.4. This value was approx. 1:17 in lesional psoriatic skin and 1:8 in oral mucosa. These observations suggest that CRABP-I and -II are regulated differently in human keratinocytes. The sharp increases in CRABP-II levels are associated with an alteration in the differentiation programme, as well as with cell response to retinoic acid overload, whereas CRABP-I might be a marker for terminal differentiation.

Animals↗

PubMed1989

Ca2+-dependent and -independent secretagogue action on gastric mucus secretion in rabbit mucosal explants.

The secretion of high-molecular weight glycoprotein was studied in rabbit antral and fundic explants in response to acetylcholine (ACh), the calcium ionophore A23187, the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), forskolin, histamine, pentagastrin, and prostaglandin E2 (PGE2). Glycoprotein secretion was measured in pulse-chase experiments by incorporation of [14C]N-acetyl-D-glucosamine into explants and quantification of the secreted high-molecular weight-labeled glycoprotein. All tested agents except histamine and pentagastrin stimulated glycoprotein secretion in a concentration-dependent manner. The response to A23187 was abolished by removal of extracellular Ca2+ and greatly reduced by the calmodulin antagonist N-(6-amino-hexyl)-l-naphthalenesulfonamide (W7). The response to ACh was abolished by equimolar concentrations of atropine and by depletion of intracellular Ca2+ stores, an effect which was reversible on addition of Ca2+, and reduced by W7. The response to forskolin and PGE2 was not significantly affected by either extracellular or intracellular Ca2+ depletion. The combination of ACh with forskolin and A23187 with TPA had a synergistic effect on secretion. The absolute dependence of cholinergic stimulation on the presence of intracellular Ca2+ and the Ca2+-independent stimulatory effect of forskolin and PGE2 suggest that gastric mucus secretion can be elicited by at least two distinct pathways.

Acetylcholine↗

PubMed1990

Minocycline-treatment of diabetic rats normalizes skin collagen production and mass: possible causative mechanisms.

Daily minocycline-treatment of streptozotocin-induced diabetic rats not only prevented a diabetes-caused atrophy of skin collagen mass (10-mos old rats), but also normalized skin collagen mass to match that of growing (ca. 1%/d) non-diabetic controls (4- and 5-mos old rats). The causative mechanism by which minocycline-treatment normalizes skin collagen mass must, in part, be related to a general anabolic effect on growth (body weight) because the effect on skin collagen mass correlates strongly to that on body weight. Consequently, a minocycline-stimulated increase of a systemic factor (such as insulin-like growth factor) is not unlikely. The anabolic effect of minocycline-treatment of diabetic rats is also expressed as a normalized cellular ribosome mass (an index of total protein synthetic capacity) and a normalized absolute rate of collagen production. (Calculation of an absolute rate was justified by an apparent maximum saturation of the prolyl-tRNA pool(s) of skin, maximum saturation obtained by the pool-flooding approach). The normalized skin ribosome amount does not, however, explain a selective effect of minocycline-treatment on collagen production as opposed to that for non-collagen protein, this selective effect measured as relative collagen production. To explain such selectivity, the inhibition of diabetes-induced excess skin collagenase activity seems unlikely. (This inference is based on results from a preliminary study indicating that recently [less than 2 h] synthesized collagen is not degraded by the excess collagenase in skin of diabetic rats). Thus, the principal collagen fraction acted on by pathologically excess collagenase might be collagen at a later stage (greater than 2 h after synthesis) in its life cycle. (Another possibility for the selective effect of minocycline on collagen production, as yet untested, is reduced intracellular procollagen degradation.) Overall, this is the first study aimed at discerning the mechanism(s) by which minocycline-treatment enhances the rate of collagen production in tissues of a diabetic rat. For future studies, the extent to which the positive effect on growth, ribosome mass, and rate of collagen production contributes to the change of collagen mass must, along with the known minocycline-inhibition of collagenase activity, be quantified. Such quantification is a prerequisite for evaluating the chemotherapeutic efficacy of minocycline-treatment on collagen-degradative diseases.

Animals↗