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Alessandra Russo

Publications and source records attributed to Alessandra Russo.

At least 19 recordsLinked to original sources

Antiproliferative activity of Pteleopsis suberosa leaf extract and its flavonoid components in human prostate carcinoma cells.

In this work we describe the chemical composition of Pteleopsis suberosa (Combretaceae) leaf extract and its biological activity against androgen-insensitive human prostate cancer cells (DU-145). The methanol extract of the plant leaves exhibited activity against tumor cell growth. Fractionation of this active extract led to the isolation and identification of sixteen flavonoids, including gallocatechin and flavonols having kaempferol, quercetin, and myricetin as aglycones. Among the myricetin derivatives, myricetin 3-O-(3''-acetyl)-alpha-L-arabinopyranoside (1) and myricetin 3-O-(4''-acetyl)-alpha- L-arabinopyranoside (2) are now reported for the first time. Six compounds, myricetin 3-O-alpha- L-rhamnopyranoside (4), myricetin 3-O-beta-D-galactopyranoside (7), myricetin 3-O-(6''-galloyl)-beta-D-galactopyranoside (9), myricetin 3-O-beta-D-xylopyranoside (10), myricetin 3-O-alpha-L-arabinofuranoside (12), and gallocatechin (14), exhibited significant activity, reducing cell vitality and inducing apoptosis via the caspase-dependent pathway in DU-145 cells that can be, in part, correlated to modulation of redox-sensitive mechanisms.

Carcinoma↗

Pannarin inhibits cell growth and induces cell death in human prostate carcinoma DU-145 cells.

In the course of our continuing search for new natural anticancer compounds for treatment and/or prevention of prostate cancer, our laboratory has focused its search on poorly investigated lichen metabolites, sphaerophorin, pannarin and epiphorellic acid-1. To this end, we treated DU-145, a cell line resembling the last stage of prostate carcinoma, with different concentrations (6-50 micromol/l) of these compounds for 72 h. Our data clearly evidenced that these lichen metabolites inhibit the growth of human prostate carcinoma DU-145 cells, but pannarin exhibits a higher effect. Our data show an induction of apoptotic death of advanced prostate cancer cells by sphaerophorin, pannarin and epiphorellic acid-1. In fact, a significant (P<0.001) increase in caspase-3 enzyme activity occurred in DU-145 cells treated with all lichen compounds at 12 and 25 micromol/l concentrations, correlated to a high DNA fragmentation, but without the disruption of the plasma membrane, as evaluated by the percentage of lactic dehydrogenase release. Alternatively, we found a low, but significant (P<0.01) lactic dehydrogenase release at higher concentrations (50 micromol/l), suggesting that in these experimental conditions sphaerophorin, pannarin and epiphorellic acid-1 induce necrosis in DU-145 cells, through the increase in reactive oxygen species generation. The experimental evidence is further confirmed by caspase-3 activity results, evidencing a reduction in the activity of this protease at a higher concentration, 50 micromol/l.

Antineoplastic Agents, Phytogenic↗

Antioxidant activity and antiproliferative action of methanolic extract of Geum quellyon Sweet roots in human tumor cell lines.

Geum quellyon Sweet, a perennial herb of the Rosaceae family, has been used in the traditional medicine of the Mapuche Amerindians of Chile to treat tooth neuralgia, gastric inflammation, prostatitis and to regulate menstruation, and for its diuretic and aphrodisiac properties. Although many benefits have been claimed for this plant, few scientific studies are available in the literature. In this study, we investigated the antioxidant activity of a methanolic extract of Geum quellyon roots. We also examined the anticancer action of this plant on Caco-2 (colon adenocarcinoma cells), DU-145 (androgen-insensitive prostate cancer cells) and KB (oral squamous carcinoma cells) human tumor cell lines. Our data showed that Geum quellyon extract, containing tannins, exhibits interesting antioxidant properties, expressed by its capacity to scavenge 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) and superoxide anion (O(2)*-), to inhibit xanthine oxidase activity, to chelate metals, and to protect plasmid DNA from cleavage induced by hydroxyl radicals (*OH) and nitric oxide (NO). These results may explain, at least in part, its use in Mapuche traditional medicine for gastric inflammation and prostatitis. The assays on human tumor cell lines demonstrated that this natural product exhibits a inhibitory effect on all human cancer cells examined, and seem to indicate that necrosis cell death is triggered in KB cells and Caco-2, while apoptotic cell demise appears to be induced in DU-145. The effect evidenced in Caco-2 cells can be in part correlated to a modulation of redox-sensitive mechanisms.

Antineoplastic Agents, Phytogenic↗

Genistin inhibits UV light-induced plasmid DNA damage and cell growth in human melanoma cells.

In recent years, genistein has received considerable attention because epidemiologic studies showed that consumption of soybean-containing diets was associated with a lower incidence of certain human cancers in Asian populations. In vitro studies further showed that such chemopreventive and antineoplastic effects were associated with the antioxidant activity of genistein and inhibitor activities on cell proliferation and angiogenesis. Genistein was shown to arrest the growth of malignant melanoma in vitro and to inhibit ultraviolet (UV) light-induced oxidative DNA damage. Recently, it has been demonstrated that genistin, as other flavonoid glycosides, is partly absorbed without previous cleavage and does not have to be hydrolyzed to be biologically active. Therefore, not only isoflavone aglycons, but also glycosides can be of physiological relevance. In the present study, we evaluated in cell-free systems the effect of genistin and daidzin on pBR322 DNA cleavage induced by hydroxyl radicals, generated from UV photolysis of hydrogen peroxide, and their superoxide anion scavenging capacity. In addition, we investigated the growth inhibitory activity of these isoflavones against human melanoma cell line (M14). Under our experimental conditions, genistin and daidzin showed a protective effect on DNA damage and exhibited a superoxide dismutase-like effect, but only genistin was able to reduce significantly the vitality of M14 cells, confirming the importance of the 5,7-dihydroxy structure in the A ring. These results suggest that also genistin, due to its antioxidant and anticarcinogenic properties, contributes to the overall biological activity of soy and could have promising applications in the field of dermatology.

Antineoplastic Agents↗

Ochratoxin A-induced DNA damage in human fibroblast: protective effect of cyanidin 3-O-beta-d-glucoside.

Ochratoxin A (OTA), a mycotoxin produced by Aspergillus ochraceus and other moulds, has recently received growing attention because of its carcinogenic, teratogenic and nephrotoxic properties in both humans and farm animals. Nevertheless, with regard to the mechanism of toxicity, the data in the literature are inconclusive. The aim of our work was to verify in human fibroblasts treated with different OTA dosages the involvement of oxidative pathway in the damage mechanism of this mycotoxin and the possible protective effect exerted by cyanidin 3-O-beta-D-glucoside (C3G), an anthocyanin present in pigmented oranges, red wines, fruits and vegetables. The addition of OTA at 25 and 50 microM concentrations for 48 h determined only a slight but significant (P<.05) increase in radical oxygen species, whereas a substantial increase in their production was observed at longer exposure, in particular, when the fibroblasts were treated with 50 microM OTA for 72 h. Under the same experimental conditions, our data showed a significant (P<.05) increase in the rupture of cellular membrane and high damage to genomic DNA, evaluated by single-cell gel electrophoresis (comet assay), thus confirming the involvement of oxidative stress in the OTA genotoxicity in agreement with other studies. Diversely, mitochondrial functionality does not appear influenced by OTA treatment. C3G (0.125, 0.250 mM) added to the cells treated with 50 microM OTA significantly reduced free radical species production and prevented genomic DNA damage.

Anthocyanins↗

Perioperative complications in acoustic neuroma (vestibular schwannoma) surgery.

OBJECTIVE: Retrospective study and review of the complications other than those related to the facial nerve and hearing, encountered in acoustic neuroma surgery. Also, an evaluation of hospital stay and its relation with various factors. STUDY DESIGN: Retrospective case review. SETTING: Tertiary neurotologic and skull base referral center. PATIENTS: A series of 707 patients who underwent surgical removal of acoustic neuroma from April 1987 to December 2001. INTERVENTIONS: The surgical approaches used were the enlarged translabyrinthine approach, the enlarged middle fossa approach, and the retrosigmoid approach. In a small number of cases, the operations were performed through other approaches. MAIN OUTCOME MEASURES: The duration of hospital stay and appearance of complications in the perioperative period along with their management. Results related to the facial nerve and hearing were not considered in this study. RESULTS: The most frequent complication was abdominal subcutaneous hematoma (site of fat harvest), which occurred in 23 patients (3.2%). Cerebrospinal fluid leak was present in 20 patients (2.8%), 15 of whom needed revision surgery. Other complications included VIth cranial nerve dysfunction in 12 cases (1.68%), subdural hematoma in 3 cases (0.4%), cerebellopontine angle hematoma in 4 cases (0.6%), cerebellar edema in 2 cases (0.28%), brainstem hematoma in 1 case (0.14%), transitory aphasia in 1 case (0.14%), and lower cranial nerve dysfunction in 1 case (0.14%). Mortality occurred in only one case (0.14%). Medical complications seldom occurred. The postoperative hospital stay ranged from 2 to 36 days, with an average of 6.4 days. The overall hospital stay diminished over time from 10.2 days in 1987 to 1990, to 4.9 days in 2001. There was a significant relation between hospital stay and tumor size, approach used, and presence/absence of complications. CONCLUSIONS: Perioperative complications in acoustic neuroma surgery do exist, but this study demonstrated how low the incidence is. The authors believe that the low percentage of complications is mainly attributable to the majority of operations being carried out in specialized clinics, where they are considered routine operations. They believe that following individualized approaches, depending on tumor size and on the preoperative function of the cranial nerves, is the proper way to reach a significant reduction in complications while maintaining a high percentage of total tumor removal. The results of this study, considered as a basis of comparison with other studies, will certainly be useful in preoperative patient counseling.

Adolescent↗

Hearing preservation surgery in vestibular schwannoma: the hidden truth.

To compare the results of hearing preservation surgeries using different approaches--the enlarged middle cranial fossa approach and the retrosigmoid approach--and different classification systems, stressing the importance of preserving "normal hearing," we performed a retrospective case review in a tertiary care medical center. The charts of 107 patients with vestibular schwannoma who underwent tumor resection were reviewed. Hearing preservation was reported according to 2 different classification systems: the modified Sanna classification and the classification of the American Academy of Otolaryngology-Head and Neck Surgery. The facial nerve results were graded according to the House-Brackmann scale. The hearing preservation rates differed markedly depending on the classification used. We conclude that hearing preservation in acoustic neuroma is a more difficult proposition than most surgeons appreciate, especially in terms of serviceable hearing.

Adolescent↗

Enlarged translabyrinthine approach for the management of large and giant acoustic neuromas: a report of 175 consecutive cases.

The translabyrinthine approach was once considered inadequate for the removal of acoustic neuromas (ANs), but that theory has few proponents today. Over the years, the translabyrinthine approach has been modified into the enlarged translabyrinthine approach, with experience and technical refinements leading to a wider access. Between April 1987 and December 2001, the Gruppo Otologico of Piacenza-Rome was able to remove 175 ANs 3 cm or larger in size from the cerebellopontine angle by adopting this modified surgical technique. These tumors represented 24.7% of all 707 ANs for which surgery was performed during the same period of time. Among the 175 cases, there was only 1 death. The incidence of complications was very low and was comparable to results previously published in the literature. Consequently, the hospital stay was short, with a mean of 7.3 days (5.1 days in the last 45 cases). The preoperative ipsilateral hearing was already compromised in 119 of the 175 cases (68%; class C/D according to the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head and Neck Surgery, 1995). From our results, we can conclude that the use of the enlarged translabyrinthine approach in AN surgery is not dependent on tumor size. On the contrary, the advantages of a low rate of morbidity and a short hospital stay are ample proof that this is the best approach for the removal of large ANs.

Cerebrospinal Fluid Rhinorrhea↗

Resveratrol and propolis as necrosis or apoptosis inducers in human prostate carcinoma cells.

Vegetables and fruit help the prevention and the therapy of several kinds of cancer because they contain micronutrients, a class of substances that have been shown to exhibit chemopreventive and chemotherapeutic activities. In the present study the effects of resveratrol (100 and 200 microM), a phytoalexin found in grapes, and of the ethanolic extract of propolis (50 and 100 microg/ml), a natural honeybee hive product, were tested in androgen-resistant prostate cancer cells (DU145), a cell line resembling the last stage of prostate carcinoma. A comparison between the activity of these micronutrients and vinorelbine bitartrate (Navelbine), a semi-synthetic drug normally used in the therapy of prostate cancer, was conducted. Several biochemical parameters were tested, such as cell viability (MTT assay), cell membrane integrity (lactate dehydrogenase release), cell redox status (nitric oxide formation, reactive oxygen species production, reduced glutathione levels), genomic DNA fragmentation (COMET assay) with special attention on the presence of apoptotic DNA damage (TUNEL test), and possible mitochondrial transmembrane potential alteration (deltapsi). Our results point out the anticancer activity of resveratrol and propolis extract in human prostate cancer, exerting their cytotoxicity through two different types of cell death: necrosis and apoptosis, respectively. The data obtained suggest the possible use of these micronutrients both in alternative to classic chemotherapy, and in combination with very low dosage of vinorelbine (5 microM).

Apoptosis↗

Nitric oxide-related toxicity in cultured astrocytes: effect of Bacopa monniera.

There is growing evidence that high concentrations of nitric oxide (NO), generated by activated astrocytes, might be involved in a variety of neurodegenerative diseases, such as Alzheimer's disease, ischemia and epilepsy. It has recently been suggested that glial cells may produce NO under superoxide radical stimulation by enzyme-independent mechanism. This suggests that also natural antioxidants may have therapeutical relevance in neurodegenerative diseases. Studies of Bhattacharya et al. have evidenced that Bacopa monniera (BM) (family Scrophulariaceae), an Ayurvedic medicinal plant clinically used for memory enhancing, epilepsy, insomnia and as a mild sedative, is able to reduce the memory-dysfunction in rat models of Alzheimer's disease, but the molecular mechanisms of this action are yet to be determined. In the present study, we examined the effect of a methanolic extract of BM on toxicity induced by the nitric oxide donor, S-nitroso-N-acetyl-penicillamine (SNAP), in culture of purified rat astrocytes. Our results indicate that, after 18 h of treatment, SNAP induced an increase in the production of reactive species, but did not induce the rupture of cellular membrane. Conversely, this NO donor induced a fragmentation of genomic DNA compared to control astrocytes. The extract of BM inhibited the formation of reactive species and DNA damage in a dose dependent manner. This data supports the traditional use of BM and indicates that this medicinal plant has a therapeutic potential in treatment or prevention of neurological diseases.

Animals↗

Effect of propolis on human cartilage and chondrocytes.

Propolis, a natural product derived from plant resins collected by the honeybees, has been used for thousands of years in folk medicine for several purposes. The extract that contains amino acids, phenolic acids, phenolic acid esters, flavonoids, cinnamic acid, terpenes and caffeic acid, possesses several biological activities such as anti-inflammatory, immunostimulatory, anti-viral and anti-bacterial. In this study, we assay the effects of propolis extract on the production of key molecules released during chronic inflammatory events as nitric oxide (NO) and glycosaminoglycans (GAGs) in cultures of human cartilaginous tissues and chondrocytes, stimulated with interleukin-1beta (IL-1beta). We observed that this natural compound and its active principle, caffeic acid phenethyl ester (CAPE), were able to contrast the harmful effects of IL-1beta. Our data clearly demonstrated the protective action of propolis in cartilage alteration, that appears greater than that elicited by indomethacin, commonly employed in joint diseases.

Anti-Inflammatory Agents, Non-Steroidal↗

Free radical scavenging capacity and protective effect of Bacopa monniera L. on DNA damage.

Bacopa monniera L. (family Scrophulariaceae) (BM) is an Ayurvedic medicine, clinically used for memory enhancing, epilepsy, insomnia and as a mild sedative. In this work, the free radical scavenging capacity of a methanol extract of BM and the effect on DNA cleavage induced by H2O2 UV-photolysis was investigated. In addition, we examined whether this plant extract is capable of reducing the hydrogen peroxide-induced cytotoxicity and DNA damage in human non-immortalized fibroblasts. It showed a dose-dependent free radical scavenging capacity and a protective effect on DNA cleavage. These results were confirmed by a significant protective effect on H2O2-induced cytoxicity and DNA damage in human non-immortalized fibroblasts. The antioxidant capacity of BM may explain, at least in part, the reported antistress, immunomodulatory, cognition-facilitating, antiinflammatory and antiaging effects produced by it in experimental animals and in clinical situations and may justify further investigation of its other beneficial properties. Moreover, this experimental evidence suggests that because of its antioxidant activity, this Ayurvedic drug may be useful in the treatment of human pathologies in which free radical production plays a key role.

Bacopa↗

Anterior and Posterior Facial Nerve Rerouting: A Comparative Study.

The infratemporal fossa type A (IFT-A) and the modified transcochlear approach are used to remove glomus jugular tumors type C and petroclival tumors extending to the prepontine cistern, respectively. Anterior rerouting is a key step in IFT-A, whereas the modified transcochlear approach involves posterior rerouting. The aim of this study was to analyze facial nerve function after application of the two procedures. One year after surgery, anterior rerouting was associated with excellent to good outcomes (grade I to III) in 94 % of the cases, while posterior rerouting was associated with good outcomes (grade III) in 70 % of the cases.

Journal Article↗

Facial nerve grafting.

OBJECTIVE: To evaluate the results of facial nerve reconstruction by means of grafting and to determine the influence of different variables on final functional recovery. STUDY DESIGN: Retrospective case review. SETTING: Tertiary otologic and skull base referral center. PATIENTS: Sixty nine patients underwent facial nerve grafting. Facial nerve tumors (24) or vestibular schwannomas (18) affected most of them. Preoperatively, 47 patients had a clinical facial nerve deficit lasting from 1 to 120 months, with a mean of 20.2 months. MAIN OUTCOME MEASURES: Final facial nerve motor function. RESULTS: Among the 56 patients with a follow-up time equal to or longer than 1 year, 26 recovered to a Grade III (46.4%), 14 to a Grade IV (25%), while 16 remained at Grade V or Grade VI according to the House-Brackmann scale. Patients with a preoperative facial nerve deficit for more than 1 year showed the lowest rate of recovery, with only 3 cases (19%) reaching Grade III. CONCLUSIONS: Duration of the preoperative facial nerve deficit emerged as the most important factor influencing final results. According to the authors' data, the 1-year period after the occurrence of the preoperative clinical deficit seemed to be the cutoff point in achieving a high rate of good postoperative recovery. Among the other factors that might have influenced the final outcome, only the underlying cause of the lesion played a significant role.

Adolescent↗

Facial nerve tumors.

OBJECTIVE: To evaluate the surgical results in primary facial nerve (FN) tumors. STUDY DESIGN: Retrospective case review. SETTING: Private neuro-otological and skull-base tertiary referral center. PATIENTS: Twenty eight consecutive patients affected by primary FN tumors that underwent surgery between December 1990 and February 2001. INTERVENTIONS: The lesions were removed through a variety of surgical approaches, depending on tumor location and extension, as well as preoperative hearing. In one case, partial removal was performed. MAIN OUTCOME MEASURES: Preoperative and postoperative FN function; preoperative and postoperative hearing level; and postoperative complications. RESULTS: Based on histologic examination, tumors were distributed as follows: 18 schwannomas, six hemangiomas, two meningiomas, and two neurofibromas. Tumor location varied, with lesions distributed along the entire length of the nerve. Facial dysfunction was the most frequently recorded symptom, followed by hearing loss. Only five patients presented a preoperative grade 1 facial function. In the remaining patients of the group, the facial deficit lasted from 2 to 120 months, with a mean of 31.2 months. Anatomic integrity of the nerve was preserved in 4 cases; all others required a nerve interruption followed by reconstruction using a sural nerve graft. The complications recorded were: one cerebrospinal fluid leak, one postoperative retraction pocket, and one external auditory canal wall resorption requiring a surgical revision. Preoperative hearing remained unchanged in 8 out of the 15 patients in whom a hearing preservation procedure was attempted. In 25 cases, a follow-up of equal to or longer than 1 year was available, with the FN functions: two grade 1, eight grade 3, nine grade 4, three grade 5, and three grade 6. Patients with a preoperative deficit lasting more than 1 year demonstrated the worst recovery. CONCLUSIONS: Primary FN tumors are rare lesions that include different histologic types. FN deficit represents the most common symptom, but it is not present in all cases. A conservative strategy is often adopted in presence of a normal preoperative facial function. When surgical management is selected, the decision on surgical approach to use depends on tumor size and location, as well as on preoperative hearing. FN integrity may be spared in rare occasions, but more frequently nerve reconstruction is required. Final facial function recovery is mainly dependent on the preoperative presence of FN deficit and its duration.

Adolescent↗

Transapical extension in difficult cerebellopontine angle tumours: preliminary report.

Difficult cerebellopontine angle (CPA) tumours namely large/giant vestibular schwannomas, vestibular schwannomas with a significant anterior extension and meningiomas of the posterior surface of the petrous bone extending anterior to the internal auditory canal (IAC) have always posed a problem for the otoneurosurgeon. Modifications of the enlarged translabyrinthine approach (ETLA) specifically aimed at dealing with these tumours are not reported. The aim of this paper is to introduce the transapical extension of ETLA which involves increased circumferential drilling around the IAC beyond 270 degrees C. The extension allows enhanced surgical control over the tumour as well as the anterior aspect of the CPA including the prepontine cistern, the Vth and VIth cranial nerves. The extension is further classified into Type I and II depending upon the extent of drilling. Type I extension entails drilling around the IAC for 300-320 degrees and is indicated for large/giant vestibular schwannomas (large vestibular schwannoma extrameatal diameter 3-39 cm, giant vestibular schwannoma extrameatal diameter >or=4 cm) and vestibular schwannomas with significant anterior extension. Type II extension involves complete drilling around the canal for 360 degrees and is indicated for meningiomas of the posterior surface of the petrous bone extending anterior to the IAC.

Cerebellar Neoplasms↗

Effect of piperine, the active ingredient of black pepper, on intestinal secretion in mice.

We have investigated the effect piperine on castor oil-stimulated fluid accumulation in the mouse small intestine. Piperine (2.5-20 mg/kg, i.p.) dose-dependently reduced castor oil-induced intestinal fluid accumulation. The inhibitory effect of piperine (10 mg/kg i.p.) was strongly attenuated in capsaicin (75 mg/kg in total, s.c.)-treated mice but it was not modified by the vanilloid receptor antagonist capsazepine (30 mg/kg i.p.). Pretreatment of mice with hexamethonium (1 mg/kg i.p.), naloxone (2 mg/kg i.p.), yohimbine (1 mg/kg i.p.) or the cannabinoid CB(1) receptor antagonist SR141716A (0.3 mg/kg i.p.) did not modify the inhibitory effect of piperine (10 mg/kg i.p.). These results suggest that piperine reduces castor oil-induced fluid secretion with a mechanism involving capsaicin-sensitive neurons, but not capsazepine-sensitive vanilloid receptors.

Alkaloids↗

The role of the phenethyl ester of caffeic acid (CAPE) in the inhibition of rat lung cyclooxygenase activity by propolis.

In this study we investigated the effect of an ethanolic extract of propolis, with and without CAPE, and some of its components on cyclooxygenase (COX) activity. Propolis (0.00003-0.03%) significantly and concentration-dependently inhibited COX activity from lung homogenate of saline- or LPS-treated rats. Same results were obtained with CAPE (0.1-100 microM). COX activity from lung homogenate of saline- or LPS-treated rats was also inhibited by galangin (0.1-100 microM), although the inhibition induced by the lowest concentration was not significant. Caffeic, ferulic, cinnamic and chlorogenic acids and pinocembrin, (0.1-100 microM) did not affect COX activity. The inhibition curves showed that CAPE and propolis were equipotent inhibitors, whereas galangin was significantly (P<0.001) less potent than propolis and CAPE. In order to better investigate the role of CAPE, we tested the action of an ethanolic extract of propolis (0.00003-0.03%) without CAPE. This extract significantly and concentration-dependently inhibited COX activity from lung homogenate of saline- or LPS-treated rats, however, it resulted to be approximately 10 times less potent than the extract containing CAPE. The analysis of the inhibition curves of the extract with and without CAPE showed a significant (P<0.001) difference. These results suggest that both CAPE and galangin contribute to the overall activity of propolis, CAPE being more effective.

Animals↗