R. P. Saxena

Immunostimulant activity of Nyctanthes arbor-tristis L.

Nyctanthes arbor-tristis L. (Oleaceae), a plant widely used in the traditional medicinal systems of India, has recently been reported to possess hepatoprotective, antileishmanial, antiviral and antifungal activities. In the present study strong stimulation of antigen specific and non-specific immunity, as evidenced by increases in humoral and delayed type hypersensitivity (DTH) response to sheep red blood cells (SRBC) and in the macrophage migration index (MMI), has been demonstrated in mice fed with 50% ethanolic extract of seeds, flowers and leaves of this plant. Maximum activity was found in the seeds in which the active principle(s) appear to be mainly associated with lipids. In flowers and leaves, however, the major activity was found in the aqueous fraction of the 50% ethanol extract. The immunostimulant substance(s) found in N. arbor-tristis L. are likely to play a role in its antiamoebic, antileishmanial, antiviral and certain other activities.

Immunostimulant activity of dry fruits and plant materials used in Indian traditional medical system for mothers after child birth and invalids.

Products of certain plants given to mothers after child birth or to invalids were studied for immunostimulant activity using the macrophage migration index (MMI) as a parameter of macrophage activation and cell-mediated immunity and haemagglutinating antibody (HA) titres and plaque-forming cell (PFC) counts as parameters of humoral immunity. Feeding of Prunus amygdalus (Almond(1)) and Buchanania lanzan (Chirronji(1)) significantly stimulated both CMI and humoral immunity in BALB/c mice as evidenced by the enhancement of MMI, HA titres, and PFC counts. Euryale ferox (Tel makhana(1)), Phoenix dactylifera (Chhohara(1)) and Zingiber officinale (Sonth(1)), however, stimulated humoral immunity to a greater extent than CMI. The observation provides scientific basis for feeding the products of above plants to mothers after child birth and to invalids with a relatively poor immune status.

Immunostimulant principles from Curculigo orchioides.

Curculigo orchioides Gaerten belongs to the family Amaryllidaceae. The rhizomes of the plants are used for the treatment of decline in strength, jaundice and asthma. Its methanolic extract has been shown to enhance phagocytic activity of macrophages. Present studies have led to the isolation of two phenolic glycosides and a purified glycoside fraction. These were studied for their effect on macrophage migration index (MMI), haemagglutination (HA) titre, plaque forming cell (PFC), PHA-induced blast transformation of lymphocytes (BTL) and delayed type hypersensitivity (DTH). Significant immunostimulant activity was found in purified glycoside-rich fraction isolated from the ethyl acetate extract. The exact structure of the active glycoside is yet to be determined. The enhancement of HA titre and PFC count on one hand and that of DTH response on the other indicates that glycoside fraction stimulates both humoral and Cell-mediated immune responses. Glycoside fraction stimulates immune response by acting both on macrophages and the lymphocytes.

Management of Giardiasis by a herbal drug `Pippali Rasayana': a clinical study

Pippali Rasayana (PR), an Indian ayurvedic drug prepared from Palash (Butea monosperma (Lamk) Kuntze; Leguminaceae) and Pippali (Piper longum L.; Piperaceae), was administered at a dose of 1 g p.o. three times daily for a period of 15 days to patients (25 treated, 25 placebo controls) suffering from giardiasis with clinical signs and symptoms, and stools positive for trophozoites/cysts of Giardia lamblia. After 15 days of drug treatment there was a complete disappearance of G. lamblia (trophozoites/cysts) from the stools of 23 out of 25 patients. General signs and symptoms of ill health and abdominal discomfort, presence of mucus, pus cells and RBCs were significantly reduced. There was a marked improvement in the clinical and haematological profile of the patients. Spontaneous recovery in 20% cases was recorded in placebo controls.

Antidyslipidemic and antioxidant activities of different fractions ofTerminalia arjuna stem bark

Terminalia arjuna (T. arjuna) stem bark was successively extracted with petroleum ether (A), solvent ether (B), ethanol (C) and water (D). The lipid lowering activity of these four fractions A, B, C, and D was evaluatedin vivo in two models viz., triton WR-1339 induced hyperlipemia in rats as well as fructose rich high fat diet (HFD) fed diabetic- dyslipidemic hamsters. Hyperlipidemia induced by triton caused marked increase in the plasma levels of total cholesterol (Tc), triglyceride (Tg) and phospholipids (PL) in rats. After treament withT. arjuna fractions A, B, C, and D at the doses of 250 mg/kg per oral (p.o.),only the ethanolic fraction (C) exerted significant lipid lowering effect as assessed by reversal of plasma levels of Tc, Tg and PL in hyperlipidemic rats. In another experiment, feeding with HFD produced marked dyslipidemia as observed by increased levels of plasma Tc, Tg, glucose (Glu), glycerol (Gly) and free fatty acids (FFA) in hamsters. After treatment withT. arjuna fractions at the doses of 250 mg/kg p.o. only two fraction (B and C) could exert significant lowering in the plasma levels of lipids and Glu. in dyslipidemic hamsters.In vitro experimentT. arjuna fractions at tested concentrations (50–500 μg/ml) inhibited the oxidative degradation of lipids in human low density lipoprotein and rat liver microsomes induced by metal ions. These fractions when tested against generation of oxygen free radicals at the concentrations (50–500 μg/ml), counteracted the formation of superoxide anions (O−2) and hydrodyl radicals (OH) in non enzymic test systems. The efficacy ofT. arjuna fractions as antidyslipidemic and antioxidant agents was found, fraction C> fraction B> fraction A.

Management of giardiasis by an immuno-modulatory herbal drug Pippali rasayana

Pippali rasayana (PR), an Ayurvedic herbal medicine, prepared from Piper longum (Pippali) and Butea monosperma (Palash), and prescribed for the treatment of chronic dysentery and worm infestations was tested for anti-giardial and immuno-stimulatory activity in mice, infected with Giardia lamblia trophozoites. It produced up to 98% recovery from the infection. The rasayana had no killing effect on the parasite in vitro. It induced significant activation of macrophages as evidenced by increased macrophage migration index (MMI) and phagocytic activity. Enhancement of host resistance could be one of the possible mechanisms contributing towards the recovery of animals from the giardial infection.

Design, synthesis and biological evaluation of α-substituted isonipecotic acid benzothiazole analogues as potent bacterial type II topoisomerase inhibitors.

The discovery and optimisation of a new class of benzothiazole small molecules that inhibit bacterial DNA gyrase and topoisomerase IV are described. Antibacterial properties have been demonstrated by activity against DNA gyrase ATPase and potent activity against Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes and Haemophilus influenzae. Further refinements to the scaffold designed to enhance drug-likeness included analogues bearing an α-substituent to the carboxylic acid group, resulting in excellent solubility and favourable pharmacokinetic properties.

Immunomodulatory Effect of Plant Extracts and Iridoid Glucosides from Nyctanthes arbortristis Against Systemic Candidiasis in Mice

AbstractProphylactic treatment with the ethanol (50%) extracts of the seed and root of the Nyctanthes arbortristis L. (p.o. once daily) provided significant (p < 0.05) protection of Swiss mice against Candida albicans systemic infection. Arbortristoside A and C (iridoid glucosides isolated from seed) at 5 mg/kg (p.o. once daily) enhanced protection. Arbortristoside C was, however, more protective (77.7%) and curative than arbortristoside A based upon increased MST (17 days) and reduced (3-log) CFU of C. albicans from kidney homogenates of treated mice compared to control. The prophylactic (-7 to -1 day) and therapeutic (+1 to +7 days post-infection) regimens (5 mg/kg) of arbortristoside A enhanced protection (71.4%), whereas, arbortristoside C was detrimental to mice. The protective effect of these extracts or fractions may possibly be because of the strong stimulatory activity of arbortristoside A and C elicited by significant (p < 0.001) increase in humoral and delayed type hypersensitivity (DTH) respon...

Regulation of glycogen metabolism by anti-dyslipidemic action of gemfibrozil and cholestyramine in a dyslipidemic-diabetic hamster model

Dyslipidemia with diabetes in hamsters, as a result of feeding with high-fat diet, caused accumulation of nonesterified fatty acid, increased lipolysis, and hyperglycemia, with decreased insulin activity. The lipid-lowering drug gemfibrozil improved insulin secretion and lowered the plasma glucose, plasma and tissue lipids viz., cholesterol, triglyceride, nonesterified fatty acids, and glycerol. Cholestyramine, a potent bile acid sequestrant was less effective than gemfibrozil in the diabetic-dyslipidemic hamster model. Treatment with the above drugs also affected glycogen metabolism by reactivation of the enzymes glycogen synthase, glucokinase, hexokinase, and glycogen phosphorylase, in liver and muscle, and reduced fat load by increasing faecal excretion of lipids. These drugs counteracted the insulin resistance by improving insulin secretion. Gemfibrozil was more effective than cholestyramine in controlling hyperglycemia, because the lipid-lowering action of the latter was mediated only by its bile acid sequestration activity.