Review Article on Molecular Mechanism of Regulation of Hypertension by Macro-elements (Na, K, Ca and Mg), Micro-elements/Trace Metals (Zn and Cu) and Toxic Elements (Pb and As).

Hypertension (HT) is a medical condition arising due to increase in blood pressure (BP) prevalent worldwide. The balanced dietary intakes of macro-elements and micro-elements including Na, K, Ca, Mg, Zn, and Cu have been described to maintain BP in humans by regulating the osmolarity of blood, cells/tissues, prevention of generation of oxidative and nitrosative stress (OANS), and endothelial damage through their functioning as important components of renin-angiotensin-aldosterone system (RAAS), antioxidant enzyme defense system, and maintenance of blood vascular-endothelial and vascular smooth muscle cell (VSMC) functions. However, inadequate/excess dietary intakes of Na/K, Ca/Mg, and Zn/Cu along with higher Pb and As exposures recognized to induce HT through common mechanisms including the followings: endothelial dysfunctions due to impairment of vasodilatation, increased vasoconstriction and arterial stiffness, blood clotting, inflammation, modification of sympathetic activity and higher catecholamine release, increased peripheral vascular resistance, and cardiac output; increased OANS due to reduced and elevated activities of extracellular superoxide dismutase and NAD(P)H oxidase, less nitric oxide bioavailability, decrease in cGMP and guanylate cyclase activity, increase in intracellular Ca2+ ions in VSMCs, and higher pro-inflammatory cytokines; higher parathyroid and calcitriol hormones; activation/suppression of RAAS resulting imbalance in blood Na+, K+, and water regulated by renin, angiotensin II, and aldosterone through affecting natriuresis/kaliuresis/diuresis; elevation in serum cholesterol and LDL cholesterol, decrease in HDL cholesterol due to defect in lipoprotein metabolism. The present study recommends the need to review simple dietary mineral intervention studies/supplementation trials before keeping their individual dietary excess intakes/exposures in consideration because their interactions lead to elevation and fall of their concentrations in body affecting onset of HT.

Exploring the efficacy of ethnomedicinal plants of Himalayan region against the malaria parasite.

ETHNOPHARMACOLOGICAL RELEVANCE: Plasmodium falciparum multi-drug resistant (MDR) strains are a great challenge to global health care. This predicament implies the urgent need to discover novel antimalarial drugs candidate from alternative natural sources. The Himalaya constitute a rich repository of medicinal plants which have been used traditionally in the folklore medicine since ages and having no scientific evidence for their activity. Crambe kotschyana Boiss. and Eremurus himalaicus Baker are used for their antipyretic and hepatoprotective properties in Kinnaur district of Himachal Pradesh, India. AIM OF THE STUDY: This study would investigate the antiplasmodial efficacy of C. kotschyana and E. himalaicus extracts, their fractions and active components using in vitro, in vivo and in silico approaches to provide a scientific insight into their activity. METHODS: The methanol extracts of C. kotschyana (CKME) and E. himalaicus (EHME) were prepared by maceration followed by fractionation using ethyl acetate. The isolation of flavonoid glycosides isorhamnetin-3, 7-di-O-glucoside from C. kotschyana and luteolin-6-C-glucoside (isoorientin) from E. himalaicus was carried out by antiplasmodial activity-guided isolation. In vitro antimalarial activity was assessed by WHO method while in vitro cytotoxicity was ascertained employing the MTT assay. Molecular docking and molecular dynamics simulation were performed using the Glide module of Schrödinger Software and Gromacs-2022 software package respectively. In vivo curative activity was assessed by Ryley and Peters method. RESULTS: The methanol extracts of both the plants illustrated the best antiplasmodial activity followed by the ethyl acetate fractions. Iso-orientin (IC50 6.49 µg/ml) and Isorhamnetin-3,7-di-O-glucoside (IC50 9.22 µg/ml) illustrated considerable in vitro activity even against P. falciparum resistant strain. Extracts/fractions as well as the isolated compounds were found to be non-toxic with CC50 > 640 µg/ml. Molecular docking studies were performed with these 2 O-glucosides against four malaria targets to understand the binding pose of these molecules and the results suggested that these molecules have selectivity for lactate dehydrogenase enzyme. CKME and EHME exhibited curative activity in vivo along with increase in Mean Survival Time of mice. CONCLUSION: The research delineated the scientific evidence that both the therapeutic herbs possessed antimalarial activity and notably, bioactive compounds responsible to exhibit the antimalarial activity have been isolated, identified and characterized. Further studies are underway to assess the antiplasmodial efficacy of isolated compounds alone and in combination with standard antimalarials.

Preparation, Standardization and Anti-plasmodial Efficacy of Novel Malaria Nosodes.

BACKGROUND: Resistance to artemisinin and its partner drugs has threatened the sustainability of continuing the global efforts to curb malaria, which urges the need to look for newer therapies to control the disease without any adverse side effects. In the present study, novel homeopathic nosodes were prepared from Plasmodium falciparum and also assessed for their in vitro and in vivo anti-plasmodial activity. METHODS: Three nosodes were prepared from P. falciparum (chloroquine [CQ]-sensitive [3D7] and CQ-resistant [RKL-9] strains) as per the Homeopathic Pharmacopoeia of India, viz. cell-free parasite nosode, infected RBCs nosode, mixture nosode. In vitro anti-malarial activity was assessed by schizont maturation inhibition assay. The in vitro cytotoxicity was evaluated by MTT assay. Knight and Peter's method was used to determine in vivo suppressive activity. Mice were inoculated with P. berghei-infected erythrocytes on day 1 and treatment was initiated on the same day. Biochemical, cytokine and histopathological analyses were carried out using standard methods. RESULTS: In vitro: the nosodes exhibited considerable activity against P. falciparum with maximum 71.42% (3D7) and 68.57% (RKL-9) inhibition by mixture nosode followed by cell-free parasite nosode (62.85% 3D7 and 60% RKL-9) and infected RBCs nosode (60.61% 3D7 and 57.14% RKL-9). The nosodes were non-toxic to RAW macrophage cell line with >70% cell viability. In vivo: Considerable suppressive efficacy was observed in mixture nosode-treated mice, with 0.005 ± 0.001% parasitemia on day 35. Levels of liver and kidney function biomarkers were within the normal range in the mixture nosode-treated groups. Cytokine analysis revealed increased levels of IL-4 and IL-10, whilst a decline in IL-17 and IFN-γ was evident in the mixture nosode-treated mice. CONCLUSION: The mixture nosode exhibited promising anti-malarial activity against P. falciparum and P. berghei. Biochemical and histopathological studies also highlighted the safety of the nosode for the rodent host. The study provides valuable insight into a novel medicament that has potential for use in the treatment of malaria.

Efficacy of Chininum Sulphuricum 30C against Malaria: An in vitro and in vivo Study.

BACKGROUND: New effective, economical and safe antimalarial drugs are urgently needed due to the development of multi-drug-resistant strains of the parasite. Homeopathy uses ultra-diluted doses of various substances to stimulate autoregulatory and self-healing processes to cure various ailments. The aim of the study was to evaluate the in vitro and in vivo antimalarial efficacy of a homeopathic drug, Chininum sulphuricum 30C. METHODS: In vitro antiplasmodial activity was screened against the P. falciparum chloroquine-sensitive (3D7) strain, and cell viability was assessed against normal human dermal fibroblasts and HepG2 cells. Suppressive, preventive and curative studies were carried out against P. berghei-infected mice in vivo. RESULTS: Chininum sulphuricum (30C) revealed good antiplasmodial activity in vitro, with 92.79 ± 6.93% inhibition against the 3D7 strain. The cell viability was 83.6 ± 0.6% against normal human dermal fibroblasts and 95.22 ± 5.1% against HepG2 cells. It also exhibited suppressive efficacy with 95.56% chemosuppression on day 7 with no mortality throughout the follow-up period of 28 days. It also showed preventive activity against the disease. Drug treatment was also safe to the liver and kidney function of the host as evidenced by biochemical studies. CONCLUSION: Chininum sulphuricum 30C exhibited considerable antimalarial activity along with safety to the liver and kidney function of the host.

Evidence for Reversal of Immunosuppression by Homeopathic Medicine to a Predominant Th1-type Immune Response in BALB/c Mice Infected with Leishmania donovani.

BACKGROUND: Visceral leishmaniasis (VL) is a neglected tropical disease that is fatal if treatment is not given. The available chemotherapeutic options are unsatisfactory, and so complementary therapies like homeopathy might be a promising approach. METHODS: A nosode from a pure axenic culture of Leishmania donovani was prepared and screened for its anti-leishmanial potential both in an in-vitro and an in-vivo experimental approach. RESULTS: Leishmania donovani amastigote promastigote nosode (LdAPN 30C) exhibited significant anti-leishmanial activity against the promastigote forms of Leishmania donovani and was found to be safe. A study conducted on VL-infected mice revealed that LdAPN 30C resolved the disease by modulating the host immune response toward the Th1 type through upregulating the pro-inflammatory cytokines (IFN-γ and IL-17) and inducing nitric oxide (NO) levels in the infected macrophages. The hepatic parasite load was also found to be significantly decreased. The nosode was found to be safe, as no histological alterations in the liver or kidney were observed in the animals treated with the LdAPN 30C. CONCLUSION: This is the first study in which an axenic culture of Leishmania donovani has been used for the preparation of a homeopathic medication. The study highlights the anti-leishmanial and immunomodulatory potential of a homeopathic nosode in experimental VL.

GC-MS screening and antiparasitic action of Putranjiva roxburghii leaves against sensitive and resistant strains of Leishmania donovani.

Looming drug resistance cases of leishmaniasis infection are an undeniably serious danger to worldwide public health, also jeopardize the efficacy of available drugs. Besides this, no successful vaccine is available till date. Since the ancient era, many plants and their parts have been used as medicines against various ailments. Hence, the importance of drug development for new molecules against Leishmania infection is significant that is a cost-effective and safer drug preferably from the natural herbal resources. We evaluated the GC-MS screening and efficacy of Putranjiva roxburghii (PR) against the sensitive and resistant promastigotes of L. donovani. GC-MS profiling revealed that the extract was rich in myo-inositol-4-C-methyl, azulene and desulphosinigrin. Quantitative investigation of phytoconstituents confirmed that PR was rich in phenols, flavonoids and terpenoids. We found an IC50 25.61 ± 0.57 µg/mL and 29.02 ± 1.21 µg/mL of PR against sodium stibogluconate sensitive and resistant strain respectively. It was found to be safer in cytotoxicity assay and generated ROS mediated oxidative stress in the parasitic cells which was evidenced by the increased and decreased levels of superoxide radicals, lipid peroxidation products, lipid bodies and levels of thiol, plasma membrane integrity respectively. Therefore, our results support the importance of P. roxburghii as a medicinal plant against L. donovani and showed potential for exploration as an antileishmanial agent.

Ethanol extract of Bergenia ciliata (Haw.) Sternb. (rhizome) impedes the propagation of the malaria parasite.

ETHNOPHARMACOLOGICAL RELEVANCE: The increasing resistant cases even against artemisinin-based combination therapy have necessitated the need to develop new antimalarials. Phytomedicinal therapy is a benchmark for malaria in the Himalayan region. As the dialect and traditional variations have been seen along with this, usage of medicinal plant, its portion (shoot and root system) and mode of preparation also varies. There is no scientific evidence available for illustrating the antiplasmodial activity of the rhizomes of Bergenia ciliata (Saxifragaceae), which is known to be an antipyretic (fever akin to malaria), hepato-protective, and also for spleen enlargement. AIM OF THE STUDY: The present study evaluates the antimalarial activity of ethanol extract of B. ciliata rhizomes (EREBC). MATERIALS AND METHODS: HPTLC was performed to identify and quantify three marker compounds in EREBC. The in vitro antimalarial activity was evaluated by schizont maturation inhibition assay. MTT assay was employed to test the cytotoxicity of EREBC. Peter's 4-day test and Peters method was employed to discern the suppressive and preventive activity of the extract respectively. RESULTS: HPTLC analysis revealed the presence of bergenin, epicatechin and gallic acid in the extract. EREBC exhibited considerable inhibition (IC50 < 5 µg/mL) of schizont maturation of both RKL-9 and MRC-2 strains of P. falciparum. EREBC was non-toxic to both HeLa cells and normal dermal fibroblasts (CC50 > 1000 µg/mL). The selectivity index was > 200 for both strains. Acute toxicity of EREBC was > 4 g/kg. EREBC exhibited considerable in vivo suppressive activity with 96.48% inhibition at 500 mg/kg in comparison to chloroquine (96.08%). The ED50 of the extract was < 50 mg/kg. No mortality was evident in mice administered with different doses of EREBC (50-500 mg/kg) throughout the follow up period of 28 days. EREBC exhibited safety to liver and kidney function of mice as observed from biochemical analysis. CONCLUSION: Overall, the study illustrates the marked efficacy and potential of EREBC as an antimalarial agent with bergenin, epicatechin and gallic acid its major constituents, which played a pivotal role in the generation of the immune response.

The Effect of Iodium 30c on Experimental Visceral Leishmaniasis.

BACKGROUND: Leishmaniasis is one of several neglected tropical diseases that warrant serious attention. A disease of socio-economically poor people, it demands safer and cheaper drugs that help to overcome the limitations faced by the existing anti-leishmanials. Complementary or traditional medicines might be a good option, with an added advantage that resistance may not develop against these drugs. Thus, the present investigation was performed to evaluate the anti-leishmanial efficacy of an ultra-diluted homeopathic medicine (Iodium 30c) in experimental visceral leishmaniasis (VL). METHODS: Compliant with strict ethical standards in animal experimentation, the study was performed in-vivo in inbred BALB/c mice which were injected intravenously with 1 × 107 promastigotes of Leishmania donovani before (therapeutic) or after (prophylactic) treatment with Iodium 30c for 30 days. In other groups of mice (n = 6 per group), amphotericin B served as positive control, infected animals as the disease control, while the naïve controls included normal animals; animals receiving only Iodium 30c or Alcohol 30c served as sham controls. The anti-leishmanial efficacy was assessed by determining the hepatic parasite load and analysing percentages of CD4+ and CD8+ T cells. Biochemical analysis and histological studies were performed to check any toxicities. RESULTS: Iodium-treated animals showed a significantly reduced parasite load (to 1503 ± 39 Leishman Donovan Units, LDU) as compared with the infected controls (4489 ± 256 LDU) (p < 0.05): thus, the mean therapeutic efficacy of Iodium 30c was 66.5%. In addition, the population of CD4+ and CD8+ T cells was significantly increased (p < 0.05) after treatment. No toxicity was observed, as evidenced from biochemical and histopathological studies of the liver and kidneys. Efficacy of Iodium 30c prophylaxis was 58.3%, while the therapeutic efficacy of amphotericin B was 85.9%. CONCLUSION: This original study has shown that Iodium 30c had significant impact in controlling parasite replication in experimental VL, though the effect was less than that using standard pharmaceutical treatment.

Protective efficacy of Chlorophytum borivilianum root extract against murine visceral leishmaniasis by immunomodulating the host responses.

BACKGROUND: The available drugs for treating visceral leishmaniasis are limited. Moreover, the disease is associated with suppression of immune function. Therefore, therapies with effective immunomodulatory agents are needed which can decrease parasitic burden and enhance adaptive immunity. OBJECTIVES: The present study was planned to evaluate the antileishmanial efficacy of crude ethanolic extract of roots of Chlorophytum borivilianum (CBREE) against murine visceral leishmaniasis through immunomodulation. MATERIALS AND METHODS: The in vitro studies were carried out to check leishmanicidal activity against promastigote form and cytotoxicity against HeLa cells. The parasite load in liver smears, immunological and biochemical changes induced by 500 and 1000 mg/kg b.wt. of CBREE were assessed on 1, 7, 14 and 21 post treatment days in infected and treated BALB/c mice. RESULTS: CBREE showed inhibitory effect on growth of promastigotes with IC50 of 28.25 µg/mL and negligible cytotoxicity. The extract was toxicologically safe in BALB/c mice when administered orally with 5 g/kg b.wt. of extract. A significant reduction in parasite load was observed along with active immunomodulation through enhanced Th1 type of immune responses and suppressed Th2 type of immune responses. CONCLUSION: The treatment with both doses showed no toxic effect as evidenced by normal liver and kidney function tests and normal histological observations of liver and kidney. Therefore, it should be further explored for its active components in pursuit of the new effective antileishmanial agents in the plant kingdom.

Immunotherapeutic potential of Codonopsis clematidea and naringenin against visceral leishmaniasis.

In an attempt to explore reasonable and impervious remedies against visceral leishmaniasis, antileishmanial potential of hydroethanolic extract of Codonopsis clematidea (HECC) and its active component, naringenin (NRG) was investigated on the basis of innocuous and immunostimulatory properties. In vitro analysis showed the ability of HECC and NRG to arrest the promastigotes in sub G0/G1 phase. Further to evaluate the protective efficacy, inbred BALB/c mice infected with L. donovani were treated with HECC and NRG for 14 days. The treated animals were sacrificed on 7th and 14th post treatment days and scrutinized for clearance of parasite, DTH response, different Th1/Th2 cytokines (IFN-γ, IL-12, TNF-α, IL-17, IL-10, IL-4), T cells and B cell responses. The expression of iNOS, NFκB and the levels of nitric oxide (NO) and reactive oxygen species was also evaluated. The toxic effect of HECC and NRG was checked in terms of biochemical parameters and histological studies. Maximum reduction in parasite load and increase in the DTH response was observed in NRG treated animals in comparison to HECC and infected control. HECC and NRG switched the host Th2 immune response to the Th1-type along with the induction of CD4+ and CD8+ T cells. CD19 B cells were found to be decreased in NRG and HECC treated animals as compared to infected control. Moreover, treatment of HECC and NRG showed no alterations in hepatic and renal enzymes which was well supported by normal architecture of liver and kidney. The mechanistic details of NRG proved that it increased the NO and ROS production by activating the NFκB and iNOS expression and thus reduced the parasite load. These findings depicted that activity of HECC might be due to the presence of NRG and that the NRG provides an encouraging alternative for the treatment of visceral leishmaniasis with the rejuvenation of immune status of the host.

Evaluation of in vitro and in vivo antileishmanial potential of bergenin rich Bergenia ligulata (Wall.) Engl. root extract against visceral leishmaniasis in inbred BALB/c mice through immunomodulation.

BACKGROUND: Medicinal plants with immunomodulatory properties can provide good alternative therapeutics for curing visceral leishmaniasis. Bergenia ligulata (Wall.) Engl. is an interesting plant with strong antioxidant, antimicrobial, immunomodulatory and hepatoprotective properties. AIM: The present study was planned to determine the antileishmanial activity of plant extract by modulating the immune responses of inbred BALB/c mice. METHODOLOGY: Bergenin, the principle active component of B. ligulata, was quantitated in crude extract by performing RP-HPLC. The therapeutic potential was assessed through in vitro antileishmanial activity and in mice model through parasite load, cytokine assays, IgG antibody levels, DTH responses, histopathology and biochemical enzyme assays. RESULTS: B. ligulata showed the presence of glycosides, saponins, carbohydrates, tannins, flavonoids and bergenin which contributed to the antileishmanial activity of extract with IC50 of 22.70 µg/mL. Furthermore, the higher dose significantly reduced the parasite load by 95.56 %. The reduction was further associated with significant enhancement of IL-12 and IFN-γ levels in comparison to IL-10 and IL-4 cytokines. The switching towards Th1 type of immune response was also confirmed by elevated antibody levels of IgG2a isotype as compared to IgG1 as well as increased DTH responses. The histology of liver and kidney further complimented the non toxic nature of plant extract in addition to its negligible toxicity on HeLa cells. CONCLUSIONS: The current study revealed the significant antileishmanial and immunomodulatory properties of this plant extract against murine visceral leishmaniasis. Further, the bioactive components will be explored to assess their efficacy for the development of safe and cost effective drug.

Cisplatin along with herbal drug treatment reduces the percentage of regulatory T cells and decreased the severity of experimental visceral leishmaniasis.

BACKGROUND: Visceral leishmaniasis is the most alarming and devastating amongst the various forms of leishmaniases. It is caused by Leishmania donovani, an obligate intracellular parasite of macrophages that survives through immunosuppression. Absence of T regulatory cells provides complete clearance of the parasite. A few immunoprophylactics have been sought to battle instinctive leishmaniasis, with fluctuating achievement. Our previous studies have shown that treatment of L. donovani infected mice with cisplatin along with herbal drugs resulted in decreased parasite load with heightened delayed type hypersensitivity responses (DTH), increased levels of IgG2a, IFN-γ, IL-2, CD4+ cells, NK 1.1 cells over that of IgG1, IL-4, 1L-10, CD8+ and CD19 in infected mice. METHODS: Along the above lines, the present study further evaluated the percentage of CD4+ CD25+ FoxP3+ T regulatory cells and ultra structural changes in kidney, liver and spleen. Cisplatin (5 mg/kg b.wt. daily for 5 days, i.p.) along with Tinosporacordifolia (100 mg/kg b.wt. daily for 15 days, p.o.) or Withaniasomnifera (350 mg/kg b.wt. daily for 15 days, p.o.) or Asparagusracemosus (650 mg/kg b.wt. daily for 15 days, p.o.) was administered to L. donovani infected BALB/c and after 30 days post treatment mice were sacrificed. RESULTS: The findings uncover a significant reduction in parasite load coupled with decreased percentage of Treg cells and no pathological changes at ultra structural level. CONCLUSION: In this manner, results acquired recommend that the decrease in percentage of T reg cells may further help the antileishmanial remedial impact of cisplatin alongside natural medications.

Antileishmanial and immunomodulatory potential of Ocimumsanctum Linn. and Cocosnucifera Linn. in murine visceral leishmaniasis.

The role of immunomodulation in the therapeutic treatment of visceral leishmaniasis has gained eminence in view of moderate to severe drawbacks of the currently available drugs like toxicity, drug resistance and prohibitive costs. The potential for modulation of the immune system of many herbal plants can be tapped to address these problems. We conducted the present research study to investigate the antileishmanial and immunomodulatory effects of Ocimum sanctum Linn. and Cocos nucifera Linn. during the progression of visceral leishmaniasis in BALB/c mouse model. The IC50 values of the ethanolic leaf extract of O. sanctum and that of the aqueous husk-fibre extract of C. nucifera against the sodium stibogluconate (SSG) susceptible strain (MHOM/IN/80/Dd8) were found to be 73.3 and 62 µg/ml respectively. On treatment of infected BALB/c mice with the extracts, we observed a reduction in hepatic parasite load by 43.63 % (O. sanctum), 65.42 % (C. nucifera) and 75.61 % (O. sanctum + C. nucifera) at 1st post treatment day (p.t.d.), while at 15th p.t.d., the reduction was 73.61 % (O. sanctum), 76.59 % (C. nucifera) and 94.12 % (O. sanctum + C. nucifera). This was accompanied by an up-scaling of the DTH response, skewing of the humoral response towards Th1 type and hepatoprotection in the form of normalization of liver function tests. Overall, administration of the extracts of these two plants in combination as compared to their administration alone rescued the affected mice from the disease greatly, which can be attributed to their antileishmanial and immunomodulatory activities.

Protection against experimental visceral leishmaniasis by immunostimulation with herbal drugs derived from Withania somnifera and Asparagus racemosus.

Visceral leishmaniasis (VL) is a vector-borne parasitic disease targeting tissue macrophages. It is among the most neglected infectious diseases. As available therapeutics for treatment of this disease have many side effects, there is a need for safer alternatives. One of the immunopathological consequences of active visceral leishmaniasis is suppression of protective T-helper (Th)-1 cells and induction of disease-promoting Th-2 cells, and thus the treatment of VL relies on immunomodulation. In the current study, herbal drugs derived as whole-plant extracts of Asparagus racemosus and Withania somnifera were used to treat Leishmania donovani-infected BALB/c mice. Keeping the scenario of immunosuppression during VL in mind, the potential of these drugs in the restoration of murine Th-1-type protective immune responses was evaluated. To investigate the propensity of these drugs to treat VL, liver parasite load, delayed-type hypersensitivity responses and parasite-specific immunoglobulin levels were studied. Various biochemical and haematological tests were also carried out. A positive-control group used the standard drug treatment of sodium stibogluconate. Treatment of infected mice with A. racemosus and W. somnifera in combination at the higher dose of 200 mg (kg body weight)(-1) not only resulted in a successful reduction in parasite load but also generated protective Th1-type immune responses with normalization of biochemical and haematological parameters, suggesting their potential as potent anti-leishmanial agents.

Tinospora cordifolia as a protective and immunomodulatory agent in combination with cisplatin against murine visceral leishmaniasis.

Effect of pure herb, Tinospora cordifolia was studied for its hepatoprotective, nephroprotective and immunomodulatory activity against high dose cisplatin treatment in Leishmania donovani infected BALB/c mice. Administration of cisplatin (5mg/kg b.wt. daily for 5 days, i.p.) reduced the parasite load in L. donovani infected BALB/c mice but produced damage in liver and kidney as manifested biochemically by an increase in serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), serum urea, serum creatinine and various electrolytes etc. These biochemical analyses were further supported by cisplatin induced morphological changes in kidney, liver and spleen. To combat this pure herb, T. cordifolia (100mg/kg b.wt. for 15 days daily) was used in combination with cisplatin in L. donovani infected BALB/c mice and it was found that all the aforementioned changes were effectively attenuated by T. cordifolia when administered in combination with cisplatin. Moreover, flow cytometric analysis of lymphocyte surface markers of T cells (CD3+, CD4+ and CD8+), NK1.1 and B cells (CD19) indicated prominent enhancement in proliferation and differentiation of lymphocytes. T. cordifolia in combination with cisplatin selectively induced Th1 type of immune response as depicted by enhanced levels of IFN-γ and IL-2 whereas Th2 specific cytokines IL-4 and IL-10 observed a moderate decline. Confirmation of Th1 polarization was further obtained from augmented levels of IgG2a over IgG1 and heightened DTH (delayed type hypersensitivity) response. Thus, our results suggest that treatment by T. cordifolia may be a critical remedy for the amelioration of adverse effects of cisplatin. Thus, this might serve as a novel combination against visceral leishmaniasis in future.

Studies on the protective and immunomodulatory efficacy of Withania somnifera along with cisplatin against experimental visceral leishmaniasis.

Visceral leishmaniasis (VL) or kala-azar continues to persist as one of the major public health problems in many tropical countries. However, no effective treatment for cure of the disease is yet available. The present study was designed to investigate the nephroprotective and immunomodulatory effect of Withania somnifera in cisplatin-treated Leishmania donovani-infected BALB/c mice. Administration of cisplatin (5 mg/kg body weight (b.wt.) daily for 5 days, i.p.) reduced the parasite load in L. donovani-infected BALB/c mice but produced damage in liver and kidney as manifested biochemically by an increase in SGOT, SGPT, serum creatinine, and blood urea nitrogen, respectively. The biochemical analysis was further substantiated by histopathological changes induced in the liver and kidney by cisplatin. However, W. somnifera (350 mg/kg b.wt. daily for 15 days, orally) when given along with cisplatin, significantly reversed these changes and enhanced the antileishmanial efficacy of the drug, cisplatin. But, when W. somnifera was given alone per se it showed less antileishmanial potential. The results also indicate that W. somnifera in combination with cisplatin resulted in significant selective upregulation of Th1 type of immunity because it guided expression of T helper cell (Th1)1 cytokines, IFN-gamma and IL-2; augmented levels of IgG2a over IgG1; and heightened DTH (delayed type hypersensitivity) responses while Th2 cytokines, IL-4, and IL-10 were downregulated. Flow cytometric analysis of W. somnifera and cisplatin-treated animals showed an increase in the percentage of T cells (CD4+, CD8+) and NK1.1 suggesting its effect on activation of T cells. These results confirm the protective and immunomodulatory activity of W. somnifera suggesting that it along with cisplatin may be a critical remedy for the amelioration of adverse effects of cisplatin. Thus, this combination appears to offer a fruitful strategy for treatment of VL.

Vaccine candidates for leishmaniasis: a review.

Leishmaniasis is a diverse group of clinical syndromes caused by protozoan parasites of the genus Leishmania. The clinical manifestation of the disease varies from self-limiting cutaneous lesions to progressive visceral disease. It is estimated that 350 million people are at risk in 88 countries, with a global incidence of 1-1.5 million cases of cutaneous and 500,000 cases of visceral leishmaniasis. The key control measures mainly rely on early case detection and chemotherapy which has been hampered by the toxicity of drugs, side-effects and by the emergence of drug resistance in parasites. Control of reservoir host and vector is difficult due to operational difficulties and frequent relapses in the host. Therefore, the development of effective and affordable vaccine against leishmaniasis is highly desirable. Although considerable progress has been made over the last decade in understanding immune mechanisms underlying potential candidate antigens, including killed, live attenuated parasites, crude parasites, pure or recombinant Leishmania proteins or DNA encoding leishmanial proteins, as well as immunomodulators from sand fly saliva, very few candidate vaccines have progressed beyond the experimental stage. As such there is no vaccine against any form of human leishmaniasis. In recent years, however, much interest has been stimulated towards vaccination against leishmaniasis focused mainly on cutaneous leishmaniasis with fewer attempts against visceral leishmaniasis.