Hypoglycaemic effects of some plant extracts are possibly mediated through inhibition in corticosteroid concentration

To unravel the possible mechanism of glucose lowering activity, effects of ten different plant extracts in the regulation of serum cortisol and glucose concentrations were evaluated in male mice. While the extracts of Inula racemosa, Boerhaavia diffusa and Ocimum sanctum decreased the serum concentration of both cortisol and glucose, Aegle marmelos, Azadirachta indica and Gymnema sylvestre extracts could exhibit hypoglycaemic activity without altering the serum cortisol concentration. It appears that the hypoglycaemic effects of former three plant extracts are mediated through their cortisol inhibiting potency, whereas the mechanism for other plant extracts could be different. Lipid-peroxidation was not enhanced by any of the plant extracts (some were in fact, antiperoxidative in nature). As I. racemosa, B. diffusa and O. sanctum exhibited antiperoxidative, hypoglycaemic and cortisol lowering activities, it is suggested that these three plant extracts may potentially regulate corticosteroid induced diabetes mellitus.

The combined effects of Trigonella and Allium extracts in the regulation of hyperthyroidism in rats

The combined effects of Trigonella foenum-graecum and Allium sativum extracts were evaluated for their ameliorative potential in the L-thyroxine-induced hyperthyroidic rat model to contribute to an understanding of interaction between the two extracts. The investigation was carried out using two different doses. A comparison was made with the response of individual plant extracts at the previously studied effective dose in adult Wistar rats rendered hyperthyroidic by daily injections of L-thyroxine (300 microg/kg body wt., s.c.). Propylthiouracil (PTU), an antithyroid drug, was used as a reference compound. Alterations in serum triiodothyronine (T3), thyroxine (T4), glucose, hepatic glucose-6-phosphatase (G-6-Pase) and oxygen consumption were studied as end parameters. Superoxide dismutase (SOD), catalase (CAT) activities, lipid peroxidation (LPO) and reduced glutathione (GSH) were examined to reveal any toxic effects of the drugs. The combined effects of Trigonella and Allium at 200 and 500 mg/kg body wt. respectively, were equipotent as compared to the individual extracts in lowering the serum concentrations of T3 and T4 in hyperthyroidic rats. Our findings reveal that some plant extracts in combination may not always prove to be synergistic. It is therefore suggested that Trigonella foenum-graecum and Allium sativum extracts may be used individually and not together in the regulation of hyperthyroidism.

Fruit extract of Emblica officinalis ameliorates hyperthyroidism and hepatic lipid peroxidation in mice

The ethanolic extract from the fruits of Emblica officinalis Gaertn (Euphorbiaceae) was investigated to evaluate its possible ameliorating effects, on the L-thyroxine (L-T4) induced hyperthyroidism and on hepatic lipid peroxidation in mice. While an increase in serum T3 (triiodothyronine) and T4 (thyroxine) concentrations, and in a thyroid dependent parameter, hepatic glucose 6-phospatase (glu-6-pase) activity was observed in L-T4 (0.5 mg/kg/d) treated animals, simultaneous oral administration of the plant extract at a dose of 250 mg/kg/d (p.o.) for 30 days in hyperthyroid mice reduced T3 and T4 concentrations by 64 and 70% respectively as compared to a standard antithyroid drug, propyl thiouracil (PTU) that decreased the levels of the thyroid hormones by 59 and 40% respectively. The plant extract also maintained nearly normal value of glu-6-pase activity in hyperthyroid mice. The plant extract also decreased hepatic lipid peroxidation (LPO) and increased the superoxide dismutase (SOD) and catalase (CAT) activities in hyperthyroid mice, exhibiting its hepatoprotective nature. Our findings suggest that the test material may potentially ameliorate the hyperthyroidism with an additional hepatoprotective benefit.

Piperine lowers the serum concentrations of thyroid hormones, glucose and hepatic 5'D activity in adult male mice

Piperine, the main alkaloid of Piper nigrum fruits, was evaluated for its thyroid hormone and glucose regulatory efficacy in adult male Swiss albino mice. Its daily oral administration (2.50 mg/kg) for 15 days lowered the serum levels of both the thyroid hormones, thyroxin (T (4)) and triiodothyronine (T (3)) as well as glucose concentrations with a concomitant decrease in hepatic 5'D enzyme and glucose-6-phospatase (G-6-Pase) activity. However, no significant alterations were observed in animals treated with 0.25 mg/kg of piperine in any of the activities studied except an inhibition in serum T (3) concentration. The decrease in T (4), T (3) concentrations and in G-6-Pase were comparable to that of a standard antithyroid drug, Proylthiouracil (PTU). The hepatic lipid-peroxidation (LPO) and the activity of endogenous antioxidants, superoxide dismutase (SOD), and catalase (CAT) were not significantly altered in either of the doses. It appears that the action of P. nigrum on thyroid functions is mediated through its active alkaloid, piperine. We also suggest that a higher dose of piperine may inhibit thyroid function and serum glucose concentration in euthyroid individuals.

Effects of Inula racemosa root and Gymnema sylvestre leaf extracts in the regulation of corticosteroid induced diabetes mellitus: involvement of thyroid hormones

The efficacy of Inula racemosa (root) and Gymnema sylvestre (leaf) extracts either alone or in combination was evaluated in the amelioration of corticosteroid-induced hyperglycaemia in mice. Simultaneously thyroid hormone levels were estimated by radio-immunoassay (RIA) in order to ascertain whether the effects are mediated through thyroid hormones or not. While the corticosteroid (dexamethasone) administration increased the serum glucose concentration, it decreased serum concentrations of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3). Administration of the two plant extracts either alone or in combination decreased the serum glucose concentration in dexamethasone induced hyperglycaemic animals. However, the administration of Inula racemosa and Gymnema sylvestre extracts in combination proved to be more effective than the individual extracts. These effects were comparable to a standard corticosteroid-inhibiting drug, ketoconazole. As no marked changes in thyroid hormone concentrations were observed by the administration of any of the plant extracts in dexamethasone treated animals, it is further suggested that these plant extracts may not prove to be effective in thyroid hormone mediated type II diabetes, but for steroid induced diabetes.

Relative efficacy of three medicinal plant extracts in the alteration of thyroid hormone concentrations in male mice

Relative importance of Bacopa monnieri (200 mg/kg), Aegle marmelos (1.00 g/kg) and Aloe vera (125 mg/kg) leaf extracts in the regulation of thyroid hormone concentrations in male mice was investigated. While serum levels of both T(3) and T(4) were inhibited by A. vera, A. marmelos extract could decrease only T(3) concentration. On the other hand, T(4) concentration was increased by B. monnieri extract suggesting its thyroid-stimulating role. When the relative potency of each plant extract was calculated in terms of percent increase or decrease in thyroid hormones, as compared to the control value, the decrease in T(3) concentration by A. marmelos was about 62% indicating its possible use in the regulation of hyperthyroidism. B. monnieri could increase T(4) concentration by 41% without enhancing hepatic lipid peroxidation (LPO) suggesting that it can be used as a thyroid-stimulating drug. In fact, hepatic LPO was decreased and superoxide dismutase (SOD) and catalase (CAT) activities were increased by B. monnieri and A. marmelos leaf extracts showing their antiperoxidative role. It is thus suggested that A. marmelos and A. vera may be used in the regulation of hyperthyroidism, while B. monnieri in hypothyroidism.

Descriptive epidemiology of haemophilia in Maharashtra, India

Secondary data on haemophilia cases in the state of Maharashtra, India were compiled and analysed. A total of 2192 haemophiliacs could be accounted from case papers and pedigrees, representing approximately 60% of the estimated number of cases in the state. Ratio of haemophilia A to haemophilia B was 4.2:1. Severe haemophiliacs constituted the majority of haemophilia A and B cases. About 70% of patients did not report any family history. Age distribution of cases suggested that the longevity of severe haemophiliacs was less than 30 years. Geographical distribution revealed clustering of cases around three established haemophilia clinics, with large parts of the state showing no cases. Although the cumulative number of cases showed an ascending trend, there was a 90% decrease in the number of cases registered between 1989 and 2000, suggesting that case recruitment from areas around the facilities had been achieved. Most cases showed delayed diagnosis, as the majority of severe haemophiliacs was being diagnosed at around 11-15 years of age. However, increasing awareness about haemophilia was reflected in a four-fold increase in referrals of severe cases over a 10-year period and increased registration of cases under 5 years of age. This study highlights that haemophilia services in India are still in their infancy, and increased awareness among healthcare providers as well as expansion of treatment facilities are still the primary areas for improvement of treatment.

Butyrate induced alterations during development of the strain ln(1)BM2(reinverted) of Drosophila melanogaster

The polytene male X chromosome of D. melanogaster, has a unique morphology, which is correlated with the property of increased transcription of the sex-linked genes of the male X chromosome. This ensures equalization of X-linked gene products between males (XY) and females (XX). Till date, an invariable correlation between the structure and transcription of the male X chromosome has been reported. However, the strain In(1)BM2(reinverted) of D. melanogaster presents a caveat to this invariable correlation. In this strain, although the male X chromosome appears puffy and diffuse, the transcription remains at the wild type level. This observation suggests the perturbation in the function of a regulator that controls the structure of the male X chromosome. In this report the response of the strain to butyrate, an inhibitor of histone deacetylase, has been studied, with specific reference to development, sex ratio and chromosome morphology of the strain. Two important conclusions arise from these experiments : (a) exposure to butyrate has more severe consequences on the development of the mutant strain and on the survival of females. (b) rearing on butyrate induced a temporal series of structural alteration of the polytene chromosome of the wild type, with the male X chromosome being most vulnerable to structural changes. The butyrate-interaction of In(1)BM2(reinverted) together with our current biochemical analyses of a chromosome coiling protein recovered from this strain, provide data for a working hypothesis explaining the sex and chromosome specific alteration of the structure of the male X chromosome of In(1)BM2(reinverted).

Inhibition of T3 production in levothyroxine-treated female mice by the root extract of Convolvulus pluricaulis

An investigation was made to evaluate the role of Convolvulus pluricaulis root extract in the regulation of hyperthyroidism in female mice. Its possible site of action was also studied. L-Thyroxine treatment for 30 days increased serum concentrations of thyroxine (T4) and triodothyronine (T3). The activity of hepatic 5'-monodeiodinase (5'-DI) and glucose-6-phosphatase (G-6-Pase) was also enhanced. On the other hand, administration of the plant extract either alone or with L-T4, decreased serum T3 concentration and the activity of hepatic 5'-DI and G-6-phase, without marked alteration in hepatic lipid peroxidation, indicating the possible regulation of hyperthyroidism by the plant extract. It appears that the action of the plant extract on thyroid function is primarily mediated through the inhibition of 5'-DI enzyme activity.

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.

Temperature-induced alteration of the polytene X chromosome structure in male larvae of the strain In(1)BM2 (reinverted) of Drosophila melanogaster

In Drosophila melanogaster, the polytene X chromosome of male third instar larva appears twice as wide as an unpaired female X chromosome or an autosome. This characteristic morphology of the male X chromosome is correlated with the increased rate of transcription of the sex-linked genes, which ensures gene dosage compensation. In male third instar larvae of the strain In(1)BM2 (reinverted), polytene nuclei manifest unusually puffy X chromosomes at 18 +/- 1 degrees C. Such 'puffy X' chromosomes are pompons, that is, despite the increased width of the chromosome, transcription remains at the wild-type level. This characteristic is a caveat to the invariable correlation between polytene chromosome puffs and transcription, and suggests that the mutant X chromosomes arise due to perturbation of a pathway that controls the structure but not the transcription of the polytene X chromosome. In this report we present evidence that the pompons of In(1)BM2 (reinverted) arise due to spiralization of the male X chromosome, which results in condensing of the chromosome. This unusual structural alteration can be induced only in male larvae of this strain, at the third instar larval stage, through temperature shifts from 24 +/- 1 degrees C to 18 +/- 1 degrees C and during recovery from cold shock. Furthermore, extract from male adult, pupae and third instar larvae can induce chromosome condensation in wild-type larvae in vitro. This new evidence not only explains the absence of correlation between chromosome width and transcription of the pompons of In(1)BM2 (reinverted), but also suggests that the chromosomal rearrangement perturbs a pathway that regulates the condensation of chromosomes.

Withania somnifera root extract in the regulation of lead-induced oxidative damage in male mouse

The importance of Withania somnifera root extract in the regulation of lead toxicity with special reference to lipid peroxidative process has been investigated in liver and kidney tissues. While lead treatment (0.5 mg kg(-1)body wt. day(-1)for 20 days) enhanced hepatic and renal lipid peroxidation (LPO), administration of plant extract in the doses of 0.7 g kg(-1)and 1.4 g kg(-1)body wt. day(-1)along with equivalent doses of lead acetate for 20 days significantly decreased LPO and increased the activities of antioxidant enzymes, viz., superoxide dismutase (SOD) and catalase (CAT), thus retaining normal peroxidative status of the tissues. We suggest that the ameliorating role of root extract of W. somnifera in the lead intoxicated mice could be the result of its antiperoxidative action.

How safe is neem extract with respect to thyroid function in male mice?

In this investigation we attempted to find out the hitherto unstudied adverse effects of neem (Azardirachta indica) leaf extract on the thyroid function of male mice. Neem leaf extract was orally administered in two different doses (40 mg and 100 mg kg(-1)day(-1)for 20 days). The extract exhibited differential effects. While the higher dose decreased serum tri-iodothyonine (T(3)) and increased serum thyroxine (T(4)) concentrations, no significant alterations of levels were observed in the lower dose group, indicating that the high concentrations of neem extract can be inhibitory to thyroid function, particularly in the conversion of T(4)to T(3), the major source of T(3)generation. A concomitant increase in hepatic lipid peroxidation (LPO) and a decrease in glucose-6-phosphatase (G-6-Pase) activity in the higher dosed group also indicated the adverse effect of neem extract despite an enhancement in the activities of two defensive enzymes, superoxide dismutase (SOD) and catalase (CAT). Thus, it appears that the higher concentration of neem extract may not be safe with respect to thyroid function and lipid peroxidation.

Role of Moringa oleifera leaf extract in the regulation of thyroid hormone status in adult male and female rats

The role of Moringa oleifera aqueous leaf extract in the regulation of thyroid hormone status, was studied in adult Swiss rats. Other than the thyroid hormone concentrations, hepatic lipid peroxidation (LPO) and the activities of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) were evaluated. In the first experiment, effects of the leaf extract (175 mg kg(-1)body wt. day(-1)for 10 days) were studied both in male and female animals. Following the administration of the extract, serum triiodothyronine (T(3)) concentration and hepatic LPO decreased with a concomitant increase in the serum thyroxine (T(4)) concentration, in female rats, while in males no significant changes were observed, suggesting that Moringa oleifera leaf extract is more effective in females than in the males. To evaluate the impact of a higher dose, in the second experiment, the study was repeated in female rats, with 350 mg kg(-1)body wt. day(-1)for the same duration. Almost similar reduction in the serum T(3)concentration (approx. 30%) and an increase in the T(4)concentration were observed suggesting the inhibiting nature of Moringa oleifera leaf extract in the peripheral conversion of T(4)to T(3), the principal source of the generation of latter hormone. As the antiperoxidative effects were exhibited only by the lower dose and percent decrease in T(3)concentration was nearly the same by both the doses, it is suggested that the lower concentration of this plant extract may be used for the regulation of hyperthyriodism. 2000 Academic Press@p$hr

Withania somnifera and Bauhinia purpurea in the regulation of circulating thyroid hormone concentrations in female mice

The effects of daily administration of Withania somnifera root extract (1.4 g/kg body wt.) and Bauhinia purpurea bark extract (2.5 mg/kg body wt.) for 20 days on thyroid function in female mice were investigated. While serum triiodothyronine (T3) and thyroxine (T4) concentrations were increased significantly by Bauhinia, Withania could enhance only serum T4 concentration. Both the plant extracts showed an increase in hepatic glucose-6-phosphatase (G-6-Pase) activity and antiperoxidative effects as indicated either by a decrease in hepatic lipid peroxidation (LPO) and/or by an increase in the activity of antioxidant enzyme(s). It appears that these plant extracts are capable of stimulating thyroid function in female mice.

Inhibition of triiodothyronine production by fenugreek seed extract in mice and rats

The effects of fenugreek seed extract on the alterations in serum thyroid hormone concentrations were studied in adult male mice and rats. Simultaneously, hepatic lipid peroxidation (LPO) and the activities of the antioxidant enzymes, viz superoxide dismutase (SOD) and catalase (CAT) were examined. Administration of methi seed extract (0.11 g kg body wt.(-1) day(-1) for 15 days) to both mice and rats significantly decreases serum triiodothyronine (T(3)) concentration and T(3)/T(4) ratio, but increases thyroxine (T(4)) levels and body weight. While hepatic LPO and CAT activities were not altered, a significant decrease in SOD activity was observed in both the animal models. These findings suggest that fenugreek seed extract induced inhibition in T(4)to T(3) conversion is not peroxidation-mediated and the inhibition in SOD activity could be the result of a decrease in the protein anabolic hormone, T3.

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.

Cadmium induced thyroid dysfunction in chicken: hepatic type I iodothyronine 5'-monodeiodinase activity and role of lipid peroxidation

Administration of cadmium chloride (2.5 mg/kg body weight/day) to chickens daily for 15 days decreased serum triiodothyronine (T3) concentration (by 68.75%) without altering the levels of serum thyroxine (T4). Hepatic 5'-monodeiodinase (5'D-I) and superoxide dismutase (SOD) activities were also decreased (by 90.47% and 20.81% respectively) with a concomitant increase in lipid peroxidation (LPO, by 206.25%). Administration of the antioxidant vitamin E (alpha-tocopherol, 5 mg/kg body weight on alternate days) to cadmium intoxicated chickens restored thyroid function by maintaining normal hepatic 5'D-I activity and serum thyroid hormone concentrations. It also prevented cadmium-induced increase in LPO. We conclude that the metal-induced inhibition in hepatic 5'D-I activity is mediated through LPO.

Preliminary studies on the inorganic constituents of some indigenous hypoglycaemic herbs on oral glucose tolerance test

Medicinal herbs used in indigenous medicines in crude forms for the management of diabetes mellitus, contain both the organic and inorganic constituents. It is known that certain inorganic mineral elements (potassium, zinc, calcium, traces of chromium, etc.) play an important role in the maintenance of normal glucose-tolerance and in the release of insulin from beta cells of islets of Langerhans. In the present study, 30 hypoglycaemic herbs were selected from indigenous folk medicines, Ayurvedic, Unani and Siddha systems of medicines. Special emphasis was given to their inorganic parts by carefully preparing ash (which contains mainly mineral elements) of the specific parts of the herbal samples under study. Next, the single dose effect on the oral glucose tolerance test (GTT) was studied using previously fasted albino rats. Similar effects were also compared with their organic parts of the concerned herbal samples in the form of 95% ethanolic extracts. In certain inorganic samples, more pronounced action (as glucose tolerance factor) were noticed than their corresponding organic parts.

Dual role of betel leaf extract on thyroid function in male mice

The effects of betel leaf extract (0.10, 0.40, 0.80 and 2.0 g kg-1 day-1 for 15 days) on the alterations in thyroid hormone concentrations. lipid peroxidation (LPO) and on the activities of superoxide dismutase (SOD) and catalase (CAT) were investigated in male Swiss mice. Administration of betel leaf extract exhibited a dual role, depending on the different doses. While the lowest dose decreased thyroxine (T4) and increased serum triiodothyronine (T3) concentrations, reverse effects were observed at two higher doses. Higher doses also increased LPO with a concomitant decrease in SOD and CAT activities. However, with the lowest dose most of these effects were reversed. These findings suggest that betel leaf can be both stimulatory and inhibitory to thyroid function, particularly for T3 generation and lipid peroxidation in male mice, depending on the amount consumed.