Berrin Zik

Effects of capsaicin on nitric oxide synthase isoforms in prepubertal rat ovary.

Abstract Nitric oxide (NO) has emerged as an important intra-ovarian regulatory factor. We investigated effects of low dose capsaicin (CAP) treatment on the different NOS isoforms in prepubertal rat ovaries. Fifteen 21-day-old female Sprague-Dawley rats were divided randomly into three groups. The first group received no treatment, the second group received 0.5 mg/kg/day CAP dissolved in the vehicle, and the third group was treated with the vehicle only. The animals were euthanized by ether inhalation after 15 days and their ovaries were excised. Ovaries were fixed in 10% neutral buffered formalin and embedded in paraffin. Sections were processed for standard immunohistochemistry using the labeled streptavidin-biotin technique for expression of nNOS, eNOS and iNOS. We demonstrated that CAP induced expression of NOS isotypes including eNOS, iNOS and nNOS in prepubertal rat ovaries. CAP may lead to release of NO either directly from nerves or indirectly by evoking release from other cells via the action of neuropeptides that are released from afferent terminals and are involved in regulating female reproductive function.

sFas levels increase in response to cisplatin-based chemotherapy in lung cancer patients

The Fas/Fas Ligand (FasL) system and survivin have counteracting roles in cell survival. Therefore, we explored the role of circulating soluble Fas (sFas) and the tissue levels of Fas and survivin with regard to response to chemotherapy in lung cancer patients. Serum samples from 52 lung cancer patients and 54 control subjects (19 benign lung disease and 35 healthy control subjects) were collected prior to and 24 and 48 h after chemotherapy. sFas was statistically significantly higher in the cancer group than that in the control groups (p < 0.001). Baseline (before chemotherapy) sFas values showed a statistically significant inverse correlation with overall survival (r = −0.599, p < 0.001). There was a significant increase in serum sFas levels 24 h after treatment (p < 0.05). Contrarily, tissue levels of Fas and survivin were not changed following the chemotherapy (p > 0,05). In conclusion, increased sFas may be an indicator of poor outcome in lung cancer patients. However, cisplatin‐based chemotherapy may not be effective via neither the Fas/FasL system nor survivin pathway. Indeed, larger sample size is required for further evaluation. Copyright

The effects of chronic low-dose capsaicin treatment on substance P levels

Capsaicin, the pungent ingredient of red pepper, is consumed in varying amounts by many ethnic groups. It serves both therapeutically and as a specific tool to investigate sensory neurons. Although effects of high capsaicin doses are well-established, systemic effects of chronic low-dose capsaicin exposure are unknown. Sprague-Dawley rats (21-day old) were injected with capsaicin (0.5 mg/kg, ip) for 6 and 19 days. Changes in Substance P (SP) levels of lung and skin were measured. Two-step sequential acetic acid extraction was used to estimate neuronal and non-neuronal SP. Six-day, but not 19-day capsaicin treatment decreased SP levels in first as well as second extractions of both tissues. Because the cumulative dose used here was much lower than the neurotoxic doses of capsaicin, initial decrease of SP levels must be due to continuous release of SP from nerve endings as well as non-neuronal tissues. The fact that SP levels returned to control values at the end of 19-day treatment demonstrates that reactive increases in SP synthesis occurred. These findings suggest that systemic exposure to low-dose capsaicin enhances sensory nerve function and also increases SP in non-neuronal tissues. In addition, significantly decreased SP levels of both tissues were observed in 40-day, compared to 27-day old rats.