PubMed Health⌕ Search

Biomedical subjects

M M Aruldhas

Publications and source records attributed to M M Aruldhas.

At least 73 records · Page 4Linked to original sources

Effect of prolactin and androgens on the prostate of bonnet monkeys, Macaca radiata: I. Nucleic acids, phosphatases, and citric acid.

The effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT), and the combinations of these androgens with PRL/Br on the growth and secretory activities of cranial and caudal prostates were studied in castrated mature monkeys, Macaca radiata. Castration decreased the body weight, organ weights, nucleic acids (DNA and RNA), phosphatases, and citric acid of cranial and caudal prostates. PRL did not alter the body weight but increased the organ weights, nucleic acids, phosphatase activities, and citric acid. Br given alone decreased the body weight and the secretory activities of prostates but caused no significant alteration in the nucleic acids. TP/DHT replacement brought back the body weight and prostatic nucleic acids to normal. It enhanced the weights, phosphatase activities, and citric acid contents of cranial and caudal prostates. PRL + TP/DHT enhanced the body weight, organ weight, and secretory activities. Br + TP/DHT decreased the body weight and secretory products of prostate but it did not produce any alteration in the organ weight and RNA content. These results suggest that PRL plays a specific stimulatory influence on monkey prostate.

Androgens↗

Interaction of sex steroids and prolactin on phosphatases, transaminases, and citric acid in the ventral prostate of male albino rats.

The interaction of androgens, testosterone propionate (TP), and dihydrotestosterone (DHT) with prolactin (PRL) and estradiol-17 beta (E2) on phosphatases, transaminases, and citric acid were studied in the ventral prostate of prepubertal and adult intact and castrated rats. None of the secretory products studied were affected by androgens or their combinations with E2/PRL in prepubertal rats except for the increase observed in organ weight and DNA content. However, in adults the hormonal combinations produced some significant changes. Among the secretory products, phosphatases, glutamate oxaloacetic transaminase (GOT), and citric acid increased significantly in adult rats after the administration of TP/DHT. Glutamate pyruvic transaminase (GPT) required PRL along with TP/DHT to show an appreciable increment in intact adult rats. The synergistic effect of PRL with androgens was observed in the adult ventral prostatic secretory acid phosphatase and citric acid. Unlike PRL, E2 in combination with androgens produced an antagonistic effect in intact adult rats, which was well pronounced in the case of prostatic weight, DNA content secretory acid phosphatase, and citric acid. None of the androgens or their combination with PRL produced any significant change in DNA content compared to intact controls.

Acid Phosphatase↗

Pattern of neutral and phospholipids in the semen of normospermic, oligospermic and azoospermic men.

Total lipid concentration was elevated in the seminal plasma of oligo- and azoospermic men. The total cholesterol content was comparatively more in the seminal plasma of azoospermic men than in that of normo- and oligospermic men. In general, infertility was associated with increased seminal concentrations for most of the neutral lipid classes. However, total phospholipids and most of the phospholipid classes were diminished in the seminal plasma of oligo- and azoospermic men and in the spermatozoa of oligospermic men. We suggest that there is a positive correlation between seminal phospholipids and fertility and a negative correlation between seminal neutral lipids and fertility.

Adult↗

Role of thyroid on testicular lipids in prepubertal, pubertal and adult rats. I. Hyperthyroidism.

The influence of thyroxine-induced hyperthyroidism on testicular neutral and phospholipids was studied in prepubertal, pubertal and adult rats. Thyroxine treatment (25 micrograms/100 g body weight) for 1 month decreased testicular total lipids, total glyceride glycerols, total cholesterol and total phospholipids. Different classes of glyceride glycerol, cholesterol and phospholipid were also diminished due to thyroxine treatment. All classes of lipids returned to the euthyroid level after the withdrawal of thyroxine treatment. The data obtained in the present study suggest that thyroid hormones have a definite influence on testicular lipid metabolism in rats.

Aging↗

Testicular lipogenic enzymes--direct effects of dexamethasone in vivo.

Specific activities of NADP-Isocitrate dehydrogenase, ATP-citrate lyase, Malate dehydrogenase and Malic enzyme were studied in dexamethasone injected and adrenalectomized prepubertal and adult rat testis. 30 days after adrenalectomy the specific activity of NADP-Isocitrate dehydrogenase increased but the specific activities of the other three enzymes decreased in both age groups. An opposite effect was observed after dexamethasone injection to intact animals. The changes observed in the specific activities of enzymes of adrenalectomized and dexamethasone treated animals reverted back to normal after dexamethasone replacement and withdrawal, respectively in adult animals. However, dexamethasone injected intact prepubertal animals did not revert back to normal after the hormone withdrawal.

ATP Citrate (pro-S)-Lyase↗

Effect of thyroxine-induced hyperthyroidism on some testicular enzymes of the pyruvate/malate cycle.

The effect of thyroxine on the specific activities of testicular enzymes of the pyruvate/malate cycle involved in lipogenesis were studied in prepubertal, pubertal and adult rats. Thyroxine (25 micrograms/100 g body weight) treatment for 1 month increased the specific activity of isocitrate dehydrogenase (NADP+) but the specific activities of ATP-citrate lyase, malate dehydrogenase and malic enzyme were inhibited. Withdrawal of thyroxine treatment from hyperthyroid rats brought back all enzyme activities to normal. The study reveals a direct, specific influence of thyroxine on different testicular enzymes of the pyruvate/malate cycle.

ATP Citrate (pro-S)-Lyase↗

Direct influence of dexamethasone in vivo on rat testicular lipogenic enzymes involved in pyruvate-malate pathway.

The changes in specific activities of NADP-isocitrate dehydrogenase, ATP-citrate lyase, Malate dehydrogenase and malic enzyme were studied in adrenalectomised and dexamethasone injected pubertal rats. One month after adrenalectomy the specific activity of NADP-isocitrate dehydrogenase increased but the specific activities of the other three enzymes decreased. An opposite effect was seen after dexamethasone administration to intact animals. The changes observed in the specific activities of enzymes of adrenalectomised and dexamethasone treated animals reverted back to normal after dexamethasone replacement and withdrawal, respectively.

ATP Citrate (pro-S)-Lyase↗

Effect of thyroidectomy on testicular enzymes of the pyruvate/malate cycle involved in lipogenesis.

The specific activities of testicular enzymes of the pyruvate/malate cycle involved in lipogenesis after thyroidectomy and thyroxine replacement were studied in prepubertal, pubertal and adult rats. Thyroidectomy induced testicular ATP citrate-lyase, malate dehydrogenase and malic enzyme activities and inhibited isocitrate dehydrogenase (NADP+) activity. Thyroxine treatment on thyroidectomized animals reverted all enzyme activities to normal. The result suggests that thyroid hormones have a differential effect on testicular enzymes of the pyruvate/malate cycle involved in lipogenesis.

ATP Citrate (pro-S)-Lyase↗

Effect of adrenalectomy and dexamethasone treatment on testicular enzymes involved in carbohydrate metabolism.

The effect of adrenalectomy on specific activities of testicular hexokinase, 6-phosphofructokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and glycogen concentration have been studied. A general increase in specific activities of all enzymes was seen after adrenalectomy in rats of all ages studied. However, lactate dehydrogenase activity and glycogen concentration in pre-pubertal rats alone were depleted with no alteration in pubertal and adult animals. This was accompanied by increased prolactin titres, but gonadotrophins and testosterone were unaltered. Dexamethasone treatment returned all enzyme activities and hormonal profiles to normal.

Adrenalectomy↗

Effect of dexamethasone on testicular enzymes of the Embden-Meyerhof and pentose-phosphate pathways.

The influence of dexamethasone on the specific activities of testicular enzymes involved in the Embden-Meyerhof and pentose-phosphate pathways was studied in pre-pubertal, pubertal and adult rats. All of the enzymes showed a decrease in specific activity after dexamethasone treatment, an effect which was most drastic in pre-pubertal animals. After cessation of treatment, the specific activity of all the enzymes reverted to normal levels, except for glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in the pre-pubertal group.

Aging↗

Specific effect of thyroid hormone on testicular enzymes involved in carbohydrate metabolism. II. Hyperthyroidism.

The influence of thyroxine on some of the key enzymes involved in glycolytic and pentose phosphate pathways in the testes of pre-pubertal; pubertal and adult rats was studied. Thyroxine-induced (25 micrograms/100 g body weight) hyperthyroidism for 1 month resulted in no change in either hexokinase (EC 2.7.1.1) or 6-phosphofructokinase (EC 2.7.1.11) activity in the testes of rats in any age group studied. However, pyruvate kinase (EC 2.7.1.40) activity was reduced significantly in the pre-pubertal and pubertal rats. Both glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44) activities were markedly increased after thyroxine treatment. Withdrawal of hormone treatment resulted in reversion of enzyme activities towards normal. The results suggest that thyroxine has an age-dependent, specific effect over testicular pyruvate kinase activity. Thyroid hormone may have a direct control over the pentose phosphate pathway in the testis.

Animals↗

Specific effect of the thyroid on testicular enzymes involved in carbohydrate metabolism. I. Hypothyroidism.

The effect of thyroidectomy (Tx) on some key enzymes involved in glycolysis and the HMP-shunt pathway were studied in the testis of pre-pubertal, pubertal and adult rats. Hexokinase (HK) and phosphofructokinase (PFK) did not show any significant change in activity after Tx. However, pyruvate kinase (PK) activity was reduced after Tx in the testis of pre-pubertal animals although in pubertal and adult rats it was not affected. Both glucose-6-phosphate dehydrogenase (G6P-DH) and 6-phosphogluconate dehydrogenase (6-PG-DH) activities were reduced after Tx and thyroxine (T4) replacement brought both enzyme activities back towards normal. The possible effect of the thyroid on testicular steroidogenesis acting through the HMP-shunt is discussed.

Animals↗

Antiproliferative effect of diallyl disulfide (DADS) on prostate cancer cell line LNCaP.

Garlic has been used throughout the world to treat coughs, toothache, earache, dandruff, hypertension, hysteria, diarrhoea, dysentery, diptheria, vaginitis and many other conditions. Garlic contains a complex mixture of oil and water-soluble organosulfur compounds. Diallyl disulfide (DADS), an oil-soluble constituent of garlic seems to be effective in reducing tumour cells originating from colon, lung and skin. Hence our present study focuses on the dose-dependent effect of DADS on an androgen-dependent prostate cancer cell line. Various concentrations of DADS ranging from 25 to 100 microM were given to LNCaP cells and the activity of lactate dehydrogenase (LDH) prostatic acid phosphatase (PAcP) and the level of prostate specific antigen were studied. DADS reduced the secretory activity of LNCaP cells with the gradual increase in dosage. DADS was found to act as a good antiproliferative agent, which was confirmed by proliferation assay. DADS also induced apoptosis and nuclear segmentation in the higher doses.

Acid Phosphatase↗

Sex steroid-induced changes in collagen of the prostate and seminal vesicle of rats.

The effects of androgen alone or in combination with estrogen or prolactin on the collagen of the prostate and seminal vesicles were studied in prepubertal and adult rats. Castration decreased the collagen content of the male accessory sex organs of both prepubertal and adult rats. Androgens showed stimulatory effects in castrated rats irrespective of the age. However, in intact animals, the stimulatory effects of androgens were evident only before puberty. Only the seminal vesicle of prepubertal rats responded to the stimulatory effect of estrogen given along with androgens. Prolactin did not elicit any appreciable effect either in the prostate or the seminal vesicles when administered along with androgens.

Aging↗