Radiotherapy and Its Impact on the Nervous System of Cancer Survivors

Radiotherapy is routinely used for the treatment of nearly all brain tumors, but it may lead to progressive and debilitating impairments of cognitive function. The growing evidence supports the fact that radiation exposure to CNS disrupts diverse cognitive functions including learning, memory, processing speed, attention and executive functions. The present review highlights the types of radiotherapy and the possible mechanisms of cognitive deficits and neurotoxicity following radiotherapy. The review summarizes the articles from Scopus, PubMed, and Web of science search engines. Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells, with minimal damage to healthy cells. While radiotherapy has yielded relative success in the treatment of cancer, patients are often plagued with unwanted and even debilitating side effects from the treatment, which can lead to dose reduction or even cessation of treatment. Little is known about the underlying mechanisms responsible for the development of these behavioral toxicities; however, neuroinflammation is widely considered as one of the major mechanisms responsible for radiotherapy-induced toxicities. The present study reviews the different types of radiotherapy available for the treatment of various types of cancers and their associated neurological complications. It also summarizes the doses of radiations used in the variety of radiotherapy, and their early and delayed side effects. Special emphasis is given to the effects of various types of radiations or late side effects on cognitive impairments.

Histone Deacetylase Inhibitors Prevented the Development of Morphine Tolerance by Decreasing IL6 Production and Upregulating μ-Opioid Receptors

BACKGROUND

Morphine tolerance on long-term usage leads to chronic pain conditions. Preclinical studies demonstrated that the upregulation of HDACs is associated with a decrease in the sensitivity of μ-opioid receptors, which results in morphine tolerance.

OBJECTIVE

The present study was designed to assess the influence of the selected known HDAC inhibitors (NMJ2 and NMJ3) on the pain tolerance induced by chronic administration of morphine in Balb/c mice.

METHODS

In the present study, morphine was administered in incremental doses 1, 2, 3.6, 6.5, 11.2, 21, and 21 mg/kg daily for seven days to develop morphine tolerance. The nociceptive thresholds, analgesia, and tolerance were assessed 30 min after morphine administration alternatively from 1st day to 7th day using the hot plate and mechanical allodynia methods.

RESULTS

The morphine control group showed a reduction in the Paw Withdrawal Threshold (PWT) and the percentage Maximum Possible Effects (MPEs). In contrast, the combination of SAHA and test drugs with morphine increased the PWT and MPEs as compared to the morphine alone group. Administration of morphine alone also showed an increase in the production of the pro-inflammatory mediator, IL-6, and down-regulation of the μ-opioid receptor in the brain tissues. Treatment with HDAC inhibitors, SAHA, and test drugs showed a reversal in these changes.

CONCLUSION

Results indicated that HDAC inhibitors were involved in the prevention of morphine tolerance in normal mice by inhibiting pro-inflammatory marker production and by increasing the sensitivity of neurons towards morphine in producing an analgesic effect in morphine tolerated mice.

Synthesis, characterization, and preclinical evaluation of new thiazolidin-4-ones substituted with p-chlorophenoxy acetic acid and clofibric acid against insulin resistance and metabolic disorder

We synthesized twenty thiazolidin-4-one derivatives, which were then characterized by standard chromatographic and spectroscopic methods. From the in vitro glucose uptake assay, two compounds behaved as insulin sensitizers, where they enhanced glucose uptake in isolated rat diaphragm. In high-carbohydrate diet-induced insulin resistant mice, these two thiazolidin-4-ones attenuated hyperglycemia, hyperinsulinemia, hypertriglyceridemia, hypercholesterolemia, and glucose intolerance. They raised the plasma leptin but did not reverse the diabetes-induced hypoadiponectinemia. Additionally, compound 3a reduced adiposity. The test compounds were also able to reverse the disturbed liver antioxidant milieu. To conclude, these two novel thiazolidin-4-ones modulated multiple mechanisms involved in metabolic disorders, reversing insulin resistance and thus preventing the development of type-2 diabetes.

Evidence-based assessment of antiosteoporotic activity of petroleum-ether extract of Cissus quadrangularis Linn. on ovariectomy-induced osteoporosis

The increasing incidence of postmenopausal osteoporosis and its related fractures have become global health issues in the recent days. Postmenopausal osteoporosis is the most frequent metabolic bone disease; it is characterized by a rapid loss of mineralized bone tissue. Hormone replacement therapy has proven efficacious in preventing bone loss but not desirable to many women due to its side-effects. Therefore we are in need to search the natural compounds for a treatment of postmenopausal symptoms in women with no toxic effects. In the present study, we have evaluated the effect of petroleum-ether extract of Cissus quadrangularis Linn. (CQ), a plant used in folk medicine, on an osteoporotic rat model developed by ovariectomy. In this experiment, healthy female Wistar rats were divided into four groups of six animals each. Group 1 was sham operated. All the remaining groups were ovariectomized. Group 2 was fed with an equivolume of saline and served as ovariectomized control (OVX). Groups 3 and 4 were orally treated with raloxifene (5.4 mg/kg) and petroleum-ether extract of CQ (500 mg/kg), respectively, for 3 months. The findings were assessed on the basis of animal weight, morphology of femur, and histochemical localization of alkaline phosphatase (ALP) (an osteoblastic marker) and tartrate-resistant acid phosphatase (TRAP) (an osteoclastic marker) in upper end of femur. The study revealed for the first time that the petroleum-ether extract of CQ reduced bone loss, as evidenced by the weight gain in femur, and also reduced the osteoclastic activity there by facilitating bone formation when compared to the OVX group. The osteoclastic activity was confirmed by TRAP staining, and the bone formation was assessed by ALP staining in the femur sections. The color intensity of TRAP and ALP enzymes from the images were evaluated by image analysis software developed locally. The effect of CQ was found to be effective on both enzymes, and it might be a potential candidate for prevention and treatment of postmenopausal osteoporosis. The biological activity of CQ on bone may be attributed to the phytogenic steroids present in it.