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Studies on hypoxoside and rooperol analogues from Hypoxis rooperi and Hypoxis latifolia and their biotransformation in man by using high-performance liquid chromatography with in-line sorption enrichment and diode-array detection.

Methanol extracts of the corms of Hypoxis rooperi and H. latifolia were studied for their hypoxoside content by an in-line sorption enrichment HPLC technique [Kruger et al., J. Chromatogr., 612 (1993) 191]. Hypoxoside is the trivial name for (E)-1,5-bis(3'-hydroxy-4'-O-beta-D-glucopyranosyl-phenyl) pent-1-en-4-yne and rooperol the aglucone obtained from beta-glucosidase treatment. Hypoxoside and rooperol analogues containing 4, 3 and 2 hydroxyl groups resolved as separate peaks with the proportion of the latter two markedly higher in H. latifolia than in H. rooperi. After oral ingestion of hypoxoside by humans, no hypoxoside or rooperol appeared in the serum. Only rooperol was present in the faeces. The serum and urine contained at least three phase II metabolite peaks. Selective enzyme hydrolysis showed that they represent the diglucuronide, disulfate and glucuronide-sulfate conjugates of all three rooperol analogues.

Alkynes↗

Changes of erythrocyte deformability in pregnancy with intrauterine fetal hypoxy.

Based on changes of erythrocyte deformability (ED) found in normal pregnancy the authors decided to study the group of pregnant women with intrauterine fetal hypoxy. We selected 47 pregnant patients between 32 and 37 weeks of pregnancy with intrauterine fetal hypoxy, which was diagnosed by Doppler umbilical cord artery blood flow measurement and/or by CTG signs of fetal hypoxy. The control group was composed of 26 healthy women in the third trimester of pregnancy with uncomplicated pregnancy and labor. ED was studied in the venous blood of pregnant women using method of colloid-osmotic hemolysis (Mirossay et al., Clin Haemorheol Microcircul, 1997). 21 newborns from the study group, treated for intrauterine fetal hypoxy, were born without symptoms of hypoxy (non verified hypoxy) and 26 newborns had a diagnosis of hypoxy, based on Apgar score, pH, base excess, bicarbonate and clinical symptoms (verified hypoxy). The entire group of 47 pregnant women with fetal hypoxy had significantly decreased ED. The changes of ED in the group with non verified hypoxy post partum were less pronounced comparing to the group with verified hypoxy. The pattern of these changes is similar to those observed one day prior to delivery in normal pregnancy. Pregnancy complicated by intrauterine fetal hypoxy is accompanied by statistically highly significant decrease of erythrocyte deformability. Interestingly similar changes can be observed in the late uncomplicated pregnancy prior to delivery.

Case-Control Studies↗

Diagnosis of traumatical and hypoxial changes of the CNS--immunohistochemical study.

The immunohistochemical detection of neuron-specific enolase and b-amyloid percursor protein were used in the group of deceased on craniocerebral injury and those who died of prolonged hypoxy without mechanical injury of the brain. Neuron-specific enolase (NSE) is produced by nerve cells and is a suitable marker for both the damage of neurons and axons. While undamaged nerve cells show immunoreactivity with the antibody anti-NSE, a significant decrease of this protein substance was noticed within two hours both in mechanical injury and in cases of prolonged hypoxy. We noticed the presence of NSE in damaged axons already several minutes after the injury whereas the hypoxy of brain without mechanical injury didn't show any or a very slight reaction of axons when examined with anti-NSE without topographic link to axonal lesion. b-amyloid percursor protein (b-APP) is a low molecular protein which the normal values of are not to be found in axons detected by standard immunohistochemistry. We noticed an increased frequency of appearance of this protein substance in axons changed by injury, while a reactive positivity to anti-body b-APP was to be found only rarely at the brain hypoxy without mechanical injury CNS.

Adolescent↗

Efficient in vitro regeneration of fertile plants from corm explants of Hypoxis hemerocallidea landrace Gaza -- the "African Potato".

We present efficient protocols for the regeneration of fertile plants from corm explants of Hypoxis hemerocallidea Fisch. and C. A. Mey. landrace Gaza, either by direct multiple shoot formation or via shoot organogenesis from corm-derived calluses. The regeneration efficiency depended on plant growth regulator concentrations and combinations. Multiple direct shoot formation with high frequency (100% with 5-8 shoots/explant) was obtained on a basal medium (BM) supplemented with 3 mg/l kinetin (BM1). However, efficient indirect regeneration occurred when corm explants were first plated on callus induction medium (BM2) with high kinetin (3 mg/l) and naphthalene acetic acid (NAA 1 mg/l), and then transferred to shoot inducing medium (BM3) containing BA (1.5 mg/l) and NAA (0.5 mg/l). Shoot regeneration frequency was 100% and 30-35 shoots per explant were obtained. The regenerated shoots were rooted on a root inducing medium (BM4) containing NAA (0.1 mg/l). Rooted plantlets were transferred to the greenhouse. The regenerants were morphologically normal and fertile. Flow cytometric analyses and chloroplast counts of guard cells suggested that the regenerants were diploid. Efficient cloning protocols described here, have the potential not only to substantially reduce the pressure on natural populations but also for wider biotechnological applications of Hypoxis hemerocallidea-an endangered medicinal plant.

2,4-Dichlorophenoxyacetic Acid↗

Antinociceptive, anti-inflammatory and antidiabetic properties of Hypoxis hemerocallidea Fisch. & C.A. Mey. (Hypoxidaceae) corm ['African Potato'] aqueous extract in mice and rats.

In order to scientifically appraise some of the anecdotal, folkloric, ethnomedical uses of Hypoxis hemerocallidea Fisch. & C.A. Mey. (Hypoxidaceae) corm ['African Potato'], the present study was undertaken to examine the antinociceptive, anti-inflammatory and antidiabetic properties of the corm's aqueous extract (APE) in mice and rats. The antinociceptive effect of APE was evaluated by 'hot-plate' and 'acetic acid' analgesic test methods in mice; while the anti-inflammatory and antidiabetic effects of the plant's extract were investigated in rats, using fresh egg albumin-induced pedal (paw) oedema, and streptozotocin (STZ)-induced diabetes mellitus models. Morphine (MPN, 10 mg/kg), diclofenac (DIC, 100 mg/kg) and chlorpropamide (250 mg/kg) were used as reference drugs for comparison. H. hemerocallidea corm aqueous extract (APE, 50-800 mg/kg i.p.) produced dose-dependent, significant (P < 0.05-0.001) antinociceptive effects against thermally- and chemically-induced nociceptive pain stimuli in mice. The plant extract (APE, 50-800 mg/kg p.o.) also significantly (P < 0.05-0.001) inhibited fresh egg albumin-induced acute inflammation, and caused dose-related, significant (P < 0.05-0.001) hypoglycaemia in normal (normoglycaemic) and diabetic rats. The results obtained in this study suggest that the antinociceptive effects of the plant's extract are peripherally- and centrally-mediated. The findings of this experimental animal study indicate that H. hemerocallidea corm aqueous extract (APE) possesses antinociceptive, anti-inflammatory and antidiabetic properties; and thus lend pharmacological support to folkloric, anecdotal uses of 'African Potato' in the treatment and/or management of painful, arthritic inflammatory conditions, as well as in the management and/or control of type-2 diabetes mellitus in some parts of southern Africa.

Analgesics↗

High-performance liquid chromatographic method for the quantitative determination of Hypoxoside in African potato (Hypoxis hemerocallidea) and in commercial products containing the plant material and/or its extracts.

Hypoxoside is a norlignan diglucoside present in the corms of African potato (Hypoxis hemerocallidea). The latter is used as a popular African traditional medicine for it's nutritional and immune-boosting properties. A reverse phase high-performance liquid chromatography method was developed and validated for the determination of hypoxoside using a mobile phase consisting of acetonitrile:water (20:80, v/v). The method was linear throughout the range of 10-100 microg/mL and provided a high degree of accuracy (100 +/- 4%). The recovery of the method was found to be 100 +/- 5%, and the precision of the study, % relative standard deviation intraday and interday (over three separate days), was better than 6.15 and 5.64%, respectively. The limits of detection and quantification were calculated to be 0.75 and 3.5 microg/mL, respectively. This method was applied to the analysis and quality control of African potato corms as well as 12 commercially available products. The daily intake of hypoxoside through traditionally prepared African potato decoction was also evaluated.

Alkynes↗

Effects of Hypoxis hemerocallidea (Fisch. & C.A. Mey.) [Hypoxidaceae] corm (African Potato) aqueous extract on renal electrolyte and fluid handling in the rat.

Current biomedical evidence suggests that Hypoxis hemerocallidea (Fisch. & C.A. Mey.) [Hypoxidaceae] (African Potato [AP]) corm extract may be useful in the management of type 2 diabetes mellitus. However, more recent reports have also indicated that certain herbal extracts attenuate the deterioration of kidney function in diabetes mellitus. Accordingly, this study investigated the effects of short- (acute) and long-term (chronic) administration of H. hemerocallidea corm aqueous extract (APE) on renal fluid and electrolyte handling in male Wistar rats. Acute effects of APE were investigated in separate groups of anesthetized rats challenged with a continuous jugular infusion of 0.077 M NaCl at 9 mL x h(- 1). After a 3.5-h equilibration period, consecutive 30-min urine collections were made over the subsequent 4 h of 1-h control, 1.5-h treatment, and 1.5-h recovery periods for measurements of urine flow, Na+, and K+ excretion rates. To establish the effects of acute APE, the extract was added to the infusate at doses of 90, 180, or 360 microg x h (-1) in separate groups of rats during the treatment period. For chronic studies, individually caged rats were administered twice with APE (30 mg x kg (-1) PO) every third consecutive day at 09h00 and 17h00 for 5 weeks. Control rats received distilled water (3 mL x kg(-1)). Urine volume and total urinary outputs of creatinine, Na+, and K+ were determined from 24-h samples. Acute infusion of APE produced a dose-dependent, significant (p < 0.01) decrease in urine flow, K+, and Na+ excretion rates. Chronic APE treatment significantly reduced urinary Na+ output between weeks 2 and 5, without affecting either urine flow or K+ excretion rates. When compared with control animals, APE significantly reduced GFR (2.54+/-0.09 mL x min (-1) vs. 1.52+/-0.02 mL x min (-1)) and increased plasma creatinine concentration (55 +/- 3 micromol x L(-1) vs. 68 +/-6 micromol x L(-1)). The results from this study suggest that the H. hemerocallidea corm aqueous extract may impair kidney function.

Analysis of Variance↗

Antiinflammatory properties of Hypoxis hemerocallidea corm (African potato) extracts in rats.

The effects of aqueous and methanolic extracts of Hypoxis hemerocallidea corm, locally known as 'African potato' in South Africa, were examined on rat paw edema induced by subplantar injections of fresh egg albumin (0.5 ml/kg). Acetyl salicylic acid (100 mg/kg p.o.) was used as the reference antiinflammatory agent for comparison. Both the aqueous and methanolic extracts of H. hemerocallidea corm (500 mg/kg p.o.) progressively reduced rat paw edema induced by the subplantar injections of fresh egg albumin. The methanolic extract produced relatively greater and more pronounced antiinflammatory effect than the aqueous extract in the experimental animal model used. However, the two extracts of African potato examined in this study were found to be less potent than acetyl salicylic acid (ASA) as an antiinflammatory agent.

Animals↗

Hypoglycemic effect of Hypoxis hemerocallidea corm (African potato) aqueous extract in rats.

Diabetes mellitus has been recognized as a clinical syndrome since ancient times, and remains a crippling global health problem today. It is a group of heterogeneous, autoimmune, hormonal and metabolic disorders, often accompanied by hypertension, hyperlipidemia and obesity. Current estimates suggest that approximately 150 million people worldwide suffer from diabetes mellitus. The present study was undertaken to examine the hypoglycemic effect of aqueous extract of Hypoxis hemerocallidea (family: Hypoxidaceae) corm (locally known as "African Potato") in normal (normoglycemic) and in streptozotocin (STZ)-treated, diabetic rats. Young adult, male Wistar rats weighing 250-300 g were used. Diabetes mellitus was induced in the group of diabetic test rats by intraperitoneal injections of STZ (90 mg/kg). In one set of experiments, graded doses of the aqueous extract of African Potato (100-800 mg/kg p.o.) were administered to 12-h fasted normal and diabetic rats. In another set of experiments, 800 mg/kg of African potato extract, a dose of the plant extract that produced maximal hypoglycemic effects in fasted normal and diabetic rats in our pilot experiments, was used. The hypoglycemic effect of this single dose was compared with those of insulin (5 micro U/kg s.c.) and glibenclamide (5 mg/kg p.o.) in 12-h fasted normal and diabetic rats. Following acute treatment, relatively moderate to high doses of African potato extract (100-800 mg/kg p.o.) produced dose-dependent, significant reductions (p < 0.05-0.001) in the blood glucose concentrations of fasted normal and diabetic rats. Similarly, insulin (5 micro U/kg s. c.) and glibenclamide (5 mg/kg p.o.) produced significant reductions (p < 0.01-0.001) in the blood glucose concentrations of the fasted normal and diabetic rats. At a dose of 800 mg/kg, the plant extract caused 30.20% and 48.54% reductions in the blood glucose concentrations of fasted normal and STZ-treated diabetic rats, respectively. While it is likely that the hypoglycemic effect of the plant extract is largely due to its phytosterols and/or sterolin content, the exact mechanism of its hypoglycemic action is still obscure and will have to await further studies. However, the results of this experimental animal study indicate that African potato possesses hypoglycemic activity; and thus lends credence to the suggested folkloric use of the herb in the control and/or management of adult-onset, type 2 diabetes mellitus in some communities of South Africa.

Administration, Oral↗

Some in vitro and in vivo cardiovascular effects of Hypoxis hemerocallidea Fisch & CA Mey (Hypoxidaceae) corm (African potato) aqueous extract in experimental animal models.

This study was undertaken to investigate some cardiovascular effects of Hypoxis hemerocallidea Fisch & CA Mey (Hypoxidaceae) corm (African potato) aqueous extract in experimental animal paradigms. The effect of the corm aqueous extract (APE) on myocardial contractile performance was evaluated on guinea-pig isolated atrial muscle strips in vitro; whereas the antihypertensive (hypotensive) effect of the plant extract was examined in hypertensive Dahl salt-sensitive rats in vivo. APE (25-400 mg/ml) produced concentration-dependent, significant (p < 0.05-0.001) negative inotropic and negative chronotropic effects on guinea-pig isolated electrically driven left, and spontaneously beating right atrial muscle preparations, respectively. Moreover, APE reduced or abolished, in a concentrationdependent manner, the positive inotropic and chronotropic responses of guinea-pig isolated atrial muscle strips induced by noradrenaline (NA, 1-100 microM) and calcium (Ca2+, 5-40 mM). The negative inotropic and chronotropic effects of APE on guinea-pig atrial muscle strips were not modified by exogenous administration of atropine (ATR, 7.5 x 10(-7)-2.5 - 10(-6) M) to the bath fluid. APE also significantly reduced (p < 0.05-0.001) or abolished in a concentration-dependent manner, the rhythmic, spontaneous, myogenic contractions of portal veins isolated from rats. Furthermore, APE caused dose-related transient but significant (p < 0.05-0.001) reductions in the systemic arterial blood pressure and heart rates of the hypertensive rats used. Although the exact mechanisms of the cardiodepressant and the transient hypotensive (antihypertensive) actions of APE could not be established in the present study, we exclude the involvement of the cholinergic system; since the extract's cardiovascular effects were resistant to atropine pretreatment. However, the results of this laboratory animal study indicated that APE caused bradycardia and brief hypotension in the mammalian experimental models used. These observations tend to suggest that the herb may be used as a natural supplementary remedy in some cases of cardiac dysfunctions and in essential hypertension. The findings of this experimental animal study lend pharmacological support to the folkloric, anecdotal uses of the African potato in the management and/or control of certain cardiac dysfunctions and essential hypertension in some rural communities of southern Africa.

Analysis of Variance↗

The effect of early hypoxy upon the development of rats and mice. 1. Preimplantation effects.

The effect of temporary hypoxy obtained by uterine vascular clamping during the preimplantation developmental period, was controlled on rats and mice (on the last day of preimplantation development). The following main effects were detected: retarded preimplantation development in rats; increased number of pathologically modified embryos and retarded oviduct-uterus migration in both species. The changes of the uterine wall due to vascular clamping disappear two days after the experimental intervention. The existence of an experimental hypoxic blastopathy is attested (at least its early, preimplantation aspect).

Animals↗

The effect of early hypoxy upon the development of rats and mice. II. Foetal effects.

The late, foetal effect of temporary hypoxy--performed by uterine vascular clamping--during the preimplantation period (day 2, 3 and 4 of pregnancy) was controlled in rats. The main detected effects were: lowering of the number of implantation sites and of the mean number of living foetuses; lowering of the mean foetal weight: increased percentage of resorptions and partial retardation of skeletal development. No structural anomalies were registered.

Animals↗

African herbal medicines in the treatment of HIV: Hypoxis and Sutherlandia. An overview of evidence and pharmacology.

In Africa, herbal medicines are often used as primary treatment for HIV/AIDS and for HIV-related problems. In general, traditional medicines are not well researched, and are poorly regulated. We review the evidence and safety concerns related to the use of two specific African herbals, which are currently recommended by the Ministry of Health in South Africa and member states for use in HIV: African Potato and Sutherlandia. We review the pharmacology, toxicology and pharmacokinetics of these herbal medicines. Despite the popularity of their use and the support of Ministries of Health and NGOs in some African countries, no clinical trials of efficacy exist, and low-level evidence of harm identifies the potential for drug interactions with antiretroviral drugs. Efforts should be made by mainstream health professionals to provide validated information to traditional healers and patients on the judicious use of herbal remedies. This may reduce harm through failed expectations, pharmacologic adverse events including possible drug/herb interactions and unnecessary added therapeutic costs. Efforts should also be directed at evaluating the possible benefits of natural products in HIV/AIDS treatment.

Alkynes↗

Effect of hydroxyethylrutosides on hypoxial-induced neutrophil adherence to umbilical vein endothelium.

A clinically available mixture of hydroxyethylrutosides (HR) was examined as a protector against endothelial cell activation by hypoxia in perfused human umbilical vein. The results showed that 500 micrograms/mL HR totally inhibited the adherence of human unstimulated neutrophils to the endothelium of umbilical vein incubated in hypoxic conditions. This inhibition was confirmed by a morphological study performed by scanning electron microscopy. In addition, neutrophils adherent to the hypoxic umbilical vein endothelium became activated, as evidence by the increased release of superoxide anions and synthesis of leukotriene B4. These processes could also be inhibited by HR. In conclusion, the results of this study suggest that the improvement in venous insufficiency observed clinically with HR could, in part, be the result of their ability to inhibit the recruitment and activation of neutrophils by endothelium activated during blood stasis.

Cell Adhesion↗

[Normobaric hypoxy-therapy of patients with bronchial asthma].

Conventional drug therapy for moderate atopic or mixed bronchial asthma was combined with normobaric hypoxytherapy (NBHT) in 32 patients (a course of 10 sessions) and was not combined in 20 control patients. Clinical results show that NBHT enhances response to conventional therapy of moderate bronchial asthma as confirmed by a significant relief of the clinical symptoms, by a significant rise of volumic and flow parameters of external respiration function, a fall in the number of CD 20+ B cells, low level of serum IgE, increased number of phagocyting neutrophils and cells carrying erythroblast antigen in peripheral blood.

Adult↗