Anand Kar

Changes in Thyroid Hormone Concentrations after Administration of Ashwagandha Root Extract to Adult Male Mice

The importance of ashwagandha root extract in the regulation of thyroid function with special reference to type‐I iodothyronine 5′‐monodeiodinase activity in mice liver has been investigated.

Achyranthes aspera elevates thyroid hormone levels and decreases hepatic lipid peroxidation in male rats

A study was made to evaluate the role of Achyranthes aspera on the changes in serum thyroid hormone concentrations and glucose levels in male rats. An attempt was also made to establish the relationship between hepatic lipid peroxidation and extract induced changes in thyroid hormone concentration, if any. Adult male Wistar rats were orally administered with the aqueous leaf extract of Achyranthes aspera at a dose of 200 mg/kg b. wt./day for 7 days. The effects of the extract on body weight, hepatic protein content, lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) activities and on serum triiodothyronine (T3), thyroxine (T4) and glucose levels were evaluated. The extract exhibited significant prothyroidic activity as it enhanced the levels of both the thyroid hormones along with an increase in serum glucose concentration, body weight and hepatic protein content. On the other hand, it decreased hepatic LPO without altering the activities of the two antioxidant enzymes, SOD and CAT significantly, suggesting a direct free radical scavenging activity of the extract. It appears that the Achyranthes aspera leaf extract is both prothyroidic and antiperoxidative in nature.

Gugulu (Commiphora mukul) induces triiodothyronine production: possible involvement of lipid peroxidation.

An investigation was made to find out the importance of gugulu (Commiphora mukul) in thyroid function of mice and to reveal the possible involvement of lipid peroxidation (LPO), if any. While no marked change in the concentrations of serum thyroxine (T4) was observed, triiodoth yronine (T3) concentration and T3/T4 ratio were enhanced following the administration of gugulu extract (0.2 g/kg b. wt./d for 15 days). A concomitant decrease in LPO was also noticed in liver, the principal site of T3 generation, suggesting that gugulu induced increase in T3 concentration is LPO mediated.

Trigonelline isolated from fenugreek seed protects against isoproterenol-induced myocardial injury through down-regulation of Hsp27 and αB-crystallin

OBJECTIVE Protective effects of trigonelline (TRG) isolated from fenugreek seed were evaluated in isoproterenol (ISO)-induced myocardial dysfunctions in adult rats and a proteomic approach was applied to understand its mechanism of action. METHODS In a preliminary experiment, effects of TRG at 20, 40, and 80 mg/kg for 20 d were studied in ISO-induced (100 mg/kg) adult rats. As 40 mg/kg was found the most effective concentration, in the final experiment, effects of 40 mg/kg of the test drug were investigated using different indices including cardiac marker enzymes, lipid peroxidation, antioxidants, cardiac histology, and electrocardiogram. Proteomic analyses were also done in cardiac myocytes. RESULTS ISO administration increased serum levels of cardiac markers (creatine kinase-MB, glutamate pyruvate transaminase, and lactate dehydrogenase) and exhibited a positive reaction in the TROP-T test. It also increased the cardiac lipid peroxidation and decreased the cellular antioxidants. Proteomic data revealed nine protein spots, seven were down-regulated and two up-regulated. The overexpressions of two small stress proteins, heat shock protein (Hsp)27 and αB crystallin were confirmed by Western blot analysis. All these alterations were restored to nearly normal values in 40 mg/kg of TRG-pretreated animals, suggesting its cardioprotective effects, which were further confirmed by histologic examinations and triphenyl tetrazolium chloride staining assay. CONCLUSION For the first time, our study revealed the down-regulation of Hsp27 and αB-crystallin and (CaMKII delta) isoform by TRG. As the test compound prevented the ISO-induced myocardial injury, its therapeutic use may further be explored.

Lead inhibits type-I iodothyronine 5'-monodeiodinase in the Indian rock pigeon Columba livia: A possible involvement of essential thiol groups

A study has been made to reveal the mode of action of lead inhibiting type-I iodothyronine 5′-monodeiodinase (5′-D) activity in the Indian rock pigeon,Columba livia. Administration of lead acetate (6 mg/kg body weight/day) for 20 days decreased 5′-D activity and glutathione content in the liver and kidney homogenates. It also reduced the serum concentration of 3, 3′, 5-triiodothyronine (T3) with a marginal increase in serum thyroxine (T4). Hepatic and renal lipid peroxidative process increased significantly following lead treatment, whereas the levels of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) were decreased. The possible involvement of lipid peroxidative process in the inhibition of 5′-D activity inColumba livia is suggested.

Regulation of Hyperthyroidism by Rauwolfia serpentina Root Extract in Mice

The aim of this study was to determine the role of Rauwolfia serpentina root extract in the regulation of hyperthyroidism in mice. In L-thyroxine (50 μg/100 g for 30 days)-treated mice, an increase in serum concentrations of both thyroid hormones (thyroxine and triiodothyronine) and in hepatic glucose-6-phosphatase activity was observed. Daily administration of the plant extract (2.5 mg kg−1) either alone or with thyroxine for 30 days decreased concentrations of both thyroid hormones, indicating the possible regulation of hyperthyroidism by the plant extract. The plant extract also decreased hepatic lipid peroxidation and increased super-oxide dismutase and catalase activity in hyperthyroid mice without hepatotoxic effects. R. serpentina root extract might be a potentially effective treatment for hyperthyroidism.

Combined Effects of Ashwagandha, Guggulu and Bauhinia Extracts in the Regulation of Thyroid Function and on Lipid Peroxidation in Mice

The combined effects of three different plant extracts (Ashwagandha root, Guggulu gum and Bauhinia bark) on the regulation of thyroid function and on lipid peroxidation have been studied in laboratory mice. Daily administration of these extracts (1.4g kg−1 Ashwagandha, 0.2 g kg−1 Guggulu and 2.5g kg−1 Bauhinia) for 30 days enhanced serum concentrations of both thyroid hormones (thyroxine and triiodothyronine) without altering hepatic lipid peroxidation, indicating that these plant extracts, given in combination, stimulate thyroid function without hepatotoxic effects. The plant extracts also induced an increase in hepatic catalase activity, further suggesting the hepatoprotective nature of the extracts. These plant extracts might be used to formulate a drug for the treatment of hypothyroidism.

Cadmium Induced Inhibition of Type-I Iodothyronine 5′-monodeiodinase in Young Cockerel: The Possible Involvement of Free Radicals

The possible involvement of free radicals in the cadmium-induced thyroid dysfunction with special reference to hepatic type-I iodothyronine 5′-monodeiodinase (5′-D) enzyme activity has been studied in cockerels. Cadmium chloride (CdCl2) administration (i.m. 0.5, 1.0 and 2.0 mg/kg body weight for 30 days) enhanced hepatic lipid peroxidation (LPO) but, decreased 5′-D activity and serum triiodothyronine (T3) concentration. Serum thyroxine (T4) was decreased only by the highest dose indicating that cadmium (Cd) is thyroid inhibitory only at higher doses. Liver appears to be highly sensitive to the metal as disruption of membrane configuration evidenced by increased hepatic LPO and inhibition of 5′-D enzyme activity were observed by all the three doses. We suggest that, Cd-induced inhibition of extrathyroidal conversion of T4 to T3, the major source of the generation of latter hormone, is dose dependent and the free radicals generated due to Cd intoxication could be one of the mechanisms involved in the inhibition 5′-D activity in hepatic tissues.

In vitro evaluation of bioremediation capacity of a commercial probiotic, Bacillus coagulans, for chromium (VI) and lead (II) toxicity

Introduction: The bioaccumulation of heavy metals including chromium (VI) (Cr (VI)) and lead (II) (Pb (II)) causes fatal toxicity in humans. Some naturally occurring bacterial genera such as Bacillus and Pseudomonas help in bioremediation of these heavy metals and some of the species of Bacillus are proven probiotics. However, no study has been conducted on Bacillus coagulans, which is a proven probiotic species of genus Bacillus. Objectives: The primary objective of the present study was to assess the potential of a proven probiotic, B. coagulans, marketed as “Sporlac-DS,” to survive in the presence of Cr (VI) and Pb (II) and its ability to reduce its concentration in vitro. Materials and Methods: The Minimum inhibitory concentration (MIC) of the organism for Cr (VI) and Pb (II) was determined followed by its biochemical and morphological characterization. Its antibiotic sensitivity and probiotic efficacy were assessed. Further, its bioremediation capacity was observed in vitro by determining the residual Cr (VI) and Pb (II) concentration after 72 h. Results: B. coagulans could tolerate up to 512 ppm concentration of Cr (VI) and had an MIC of 128 ppm for Pb (II). After 72 h, the organism reduced 32 ppm Cr (VI) and 64 ppm Pb (II) by 93% and 89%, respectively. When B. coagulans was studied before and after growing on Cr (VI) and Pb (II) for 24 h, an increase was seen in sensitivity toward the tested antibiotics whereas no change was observed in morphological and biochemical characters. It also showed no change in their bile and acid tolerance, indicating that it retains its probiotic efficacy. Conclusion: The tested probiotic B. coagulans may have a potential role in bioremediation of Cr (VI) and Pb (II), in vivo.