Qualitative and quantitative studies of erythropoiesis in 23 patients with hypothyroidism and 21 patients with hyperthryoidism included routine hematologic evaluation, bone marrow morphology, status of serum iron, B12 and folate red blood cell mass and plasma volume by radioisotope methods, erythrokinetics and radiobioassay of plasma erythropoietin. A majority of patients with the hypothyroid state had significant reduction in red blood cell mas per kg of body weight. The presence of anemia in many of these patients was not evident from hemoglobin and hematocrit values due to concomitant reduction of plasma volume. The erythrokinetic data in hypothyroid patients provided evidence of significant decline of the erythropoietic activity of the bone marrow. Erythroid cells in the marrow were depleted and also showed reduced proliferative activity as indicated by lower 3H-thymidine labeling index. Plasma erythropoietin levels were reduced, often being immeasurable by the polycythemic mouse bioassay technique. These changes in erythropoiesis in the hypothyroid state appear to be a part of physiological adjustment to the reduced oxygen requirement of the tissues due to diminished basal metabolic rate. Similar investigations revealed mild erythrocytosis in a significant proportion of patients with hyperthyroidism. Failure of erythrocytosis to occur in other patients of this group was associated with impaired erythropoiesis due to a deficiency of hemopoietic nutrients such as iron, vitamin B12 and folate. The mean plasma erythropoietin level of these patients was significantly elevated; in 4 patients the levels were in the upper normal range whereas in the rest, the values were above the normal range. The bone marrow showed erythyroid hyperplasia in all patients with hyperthyroidism. The mean 3H-thymidine labeling index of the erythroblasts was also significantly higher than normal in hyperthyroidism; in 8 patients the index was within the normal range whereas in the remaining 13 it was above the normal range. Erythrokinetic studies also provided evidences of increased erythropoietic activity in the bone marrow. It is postulated that thyroid hormones stimulate erythropoiesis, sometimes leading to erythrocytosis provided there is no deficiency of hemopoietic nutrients. Stimulation of erythropoiesis by thryoid hormones appears to be mediated through erythropoietin.

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The effects of oil extract of garlic (Allium sativum Linn.) on different primary and secondary osteoporotic marker changes were tested in an ovariectomized rat model of osteoporosis. Experiments were performed on three different rat models: sham-operated control, ovariectomized and ovariectomized supplemented with garlic oil. In ovariectomized group, there has been a significant increase in different relative organ weights compared to sham-operated control, while the uterine weight was found to be decreased. Supplementation with oil extract of garlic could effectively reverse these changes. Also low bone densities that developed in the ovariectomized group were significantly recovered in the garlic oil supplemented group. In our study, the development of high rate of bone turnover and osteoporosis in the ovariectomized animals were confirmed by significant alteration of serum alkaline phosphatase activity, serum tartrate resistant acid phosphatase activity, urinary excretion of calcium, phosphate, hydroxyproline and urinary calcium to creatinine ratio, when compared with the sham-operated control group. Garlic oil extract supplementation, apart from its unique influence in lowering blood cholesterol, could also prevent ovariectomy-induced rise in all the above-mentioned marker changes. The results of this study emphasize that oil extract of garlic possibly has a positive role in suppressing ovariectomy-induced bone resorption.

The effect of folic acid and folic acid + vitamin B12 supplementation upon short‐term arsenic‐induced systemic and pancreatic islet cell mitochondria oxidative stress was investigated in male rats. Arsenic trioxide was administered orally at a dose of 3 mg kg body weight−1 day−1 for 30 days, and folic acid and vitamin B12 were administered at a dose of 36 and 0.63 μg kg body weight−1 day−1, respectively, for 30 days. Compared to control, arsenic‐treated group showed a significant increase in the levels of systemic oxidative markers, malondialdehyde (MDA), nitric oxide (NO), and hydroxyl radical (OH−) formation, which were found decreased significantly after supplementation either with folic acid or a combination of folic acid + vitamin B12. Similar supplementations were found effective against arsenic‐induced oxidative marker changes (MDA, NO, and OH−) in pancreatic islet cell mitochondria. Also, low activities of antioxidant defense enzymes such as superoxide dismutase and catalase, and level of antioxidant glutathione, all could regain significantly on supplementations both against systemic and islet cell mitochondria oxidative stress. Results of agarose‐gel electrophoresis of DNA from lymphocytes and islet cells of arsenic‐exposed rats showed DNA smearing, which could be reduced with simultaneous administration either with folic acid or a combination of folic acid + vitamin B12. Significantly, similar supplementations were found effective in increasing the urinary clearance of arsenic. Together, these results indicate that folic acid and vitamin B12 may be effective to reduce the arsenic‐induced damage at molecular target level. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.

The present study was undertaken to examine the effects of an oil extract of garlic on the in vivo intestinal transference of calcium, and also to verify its role in maintaining the bone mineral content and bone tensile strength in an ovariectomized rat model of osteoporosis. The results suggest that, in this experimental model, oil extract of garlic promotes intestinal transference of calcium by modulating the activities of both intestinal alkaline phosphatase and Ca(2+) activated ATPase. Also the observed low bone mineral content and low bone tensile strength in these rats were significantly restored by garlic oil supplementation. Further, garlic oil supplementation was able to revive partially the bilateral ovariectomy-induced decrease in the serum estrogen titer. The serum parathyroid hormone level, however, was found unaltered in these rats. The garlic oil supplemented partial recovery in serum estrogen titer in bilaterally ovariectomized rat was found to be persistently associated with enhanced calcium transference and better preservation of bone mineral content. The results of this study propose that the phytoestrogenic efficacy of an oil extract of garlic prevents ovarian hormone deficiency induced bone mineral loss possibly by promoting intestinal transference of calcium through the partial revival of the serum estrogen titer.

The protective action of aqueous black tea extract (BTE) against ovariectomy-induced oxidative stress of mononuclear cells and its associated progression of bone loss was demonstrated in this study. Eighteen female adult 6-month-old Wistar albino rats were divided into three groups: sham-control (A), bilaterally ovariectomized (B) and bilaterally ovariectomized + BTE supplemented (C). Studies included the measurement of oxidative (nitric oxide, lipid peroxidation) and antioxidative (superoxide dismutase, catalase) markers, inflammatory cytokines (IL-6, TNF-alpha), osteoclast differentiation factor (RANKL) and bone resorption markers (tartrate-resistant acid phosphatase and hydroxyproline). Also quantitative histomorphometry and histological studies were undertaken. The bone breaking force was measured. The results indicate that BTE was effective in preserving and restoring skeletal health by reducing the number of active osteoclasts. Such changes with BTE supplementation were steadily linked with the reduced oxidative stress of mononuclear cells, serum levels of bone resorbing cytokines, osteoclast differentiation factor and resorption markers. The results of the bone breaking force, histological and histomorphometric analyses further supported the hypothesis. This study suggests that BTE has both protective and restorative actions against ovariectomy-induced mononuclear cell oxidative stress and associated bone loss.