Protective Effects of Tinospora crispa Stem Extract on Renal Damage and Hemolysis during Plasmodium berghei Infection in Mice

Therapeutic activity of eugenol towards mitigation of anaemia and oxidative organ damage caused by Plasmodium berghei

The parasite responsible for causing malaria infection, Plasmodium, is known to exhibit resistance to a number of already available treatments. This has prompted the continue search for new antimalarial drugs ranging from medicinal plant parts to synthetic compounds. In lieu of this, the mitigative action of the bioactive compound, eugenol towards P. berghei-induced anaemia and oxidative organ damage was investigated following a demonstration of in vitro and in vivo antiplasmodial effects. Mice were infected with chloroquine-sensitive strain of P. berghei and thereafter treated with eugenol at doses of 10 and 20 mg/kg body weight (BW) for seven days. The packed cell volume and redox sensitive biomarkers in the liver, brain and spleen were measured. Our result demonstrated that eugenol significantly (p < 0.05) ameliorated the P. berghei-associated anaemia at a dose of 10 mg/kg BW. In addition, the compound, at a dose of 10 mg/kg BW, significantly (p < 0.05) alleviated the P. berghei-induced organ damage. This evidently confirmed that eugenol plays an ameliorative role towards P. berghei-related pathological alterations. Hence, the study opens up a new therapeutic use of eugenol against plasmodium parasite.

An updated and comprehensive review on the ethnomedicinal uses, phytochemistry, pharmacological activity and toxicological profile of Tinospora crispa (L.) Hook. f. & Thomson

Tinospora crispa (L.) Hook. f. & Thomson (Menispermaceae) is a plant indigenous to Africa and South-East Asia. It is widely used in ethnomedicine to alleviate various diseases including hypertension, diabetes, rheumatism, jaundice, inflammation, fever, fractures, scabies, and urinary disorders. A total of 167 phytoconstituents, belonging to 12 different chemical categories, including alkaloids, flavonoids, terpenoids, and phenolic compounds have thus far been isolated from various parts of T. crispa. Numerous in vitro and in vivo investigations have already established the antidiabetic, anticancer, antiparasitic, antimicrobial, immunomodulatory, hepatoprotective, analgesic, antipyretic, antihyperuricemic, and pesticidal activity of this plant, as well as its effects on the cardiac and the central nervous system. Most pharmacological investigations to date have been carried out on plant extracts and fractions. The exact identity of the phytoconstituents responsible for the observed biological effects and their mode of action at the molecular level are yet to be ascertained. Toxicological studies have demonstrated that T. crispa is relatively safe, although dose-dependent hepatotoxicity is a concern at high doses. This review presents a comprehensive update and analysis on studies related to the ethnomedicinal uses, phytochemistry, pharmacological activity and toxicological profile of T. crispa. It provides some critical insights into the current scientific knowledge on this plant and its future potential in pharmaceutical research.

Hepatoprotective activity of Eucalyptus camaldulensis extract in murine malaria mediated by suppression of oxidative and inflammatory processes

Herbal extracts are promising agents against various parasitic diseases, such as malaria. This study aimed to evaluate the ameliorative action of Eucalyptus camaldulensis extract (ECE) against hepatic damage caused by Plasmodium chabaudi infection. Mice were allocated into five groups as follows: two groups served as the control non-infected groups that received distilled water and ECE, respectively; subsequent three groups were infected with 106 P. chabaudi parasitized erythrocytes; the last two groups were infected with the parasite and then treated with ECE and chloroquine. On day 8 post-infection, the parasite count increased inside erythrocytes (59.4% parasitemia in the infected group). Parasitemia was successfully reduced to 9.4% upon ECE treatment. Phytochemical screening using GC mass spectrometry revealed that ECE contained 23 phytochemical components. Total phenolics and flavonoids in ECE were 104 ± 2 and 7.1± 3 µg/mL, respectively, with 57.2% antioxidant activity. ECE ameliorated changes in liver histopathology and enzymatic activity of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. In addition, ECE prevented oxidative damage induced by the parasite in the liver, as evidenced by the change in the liver concentrations of glutathione, nitric oxide, malondialdehyde, and catalase. Moreover, ECE was able to regulate the expression of liver cytokines, interleukins-1β and 6, as well as IFN-γ mRNA. ECE possesses antiplasmodial, antioxidant, and anti-inflammatory activity against liver injury induced by the parasite P. chabaudi.

Phytochemical Constituents, Antimalarial Efficacy, and Protective Effect of Eucalyptus camaldulensis Aqueous Leaf Extract in Plasmodium berghei-Infected Mice

This study examined the bioactive components of Eucalyptus camaldulensis aqueous leaf extracts and their protective effects on liver and renal function in a Plasmodium berghei-induced albino mouse model of malarial infection. The results showed that E. camaldulensis extracts are rich in phytochemicals, including flavonoids, phenols, saponin, terpenes, and tannin. Four days after infection with malaria, elevated parasitemia levels in untreated control mice dropped by 4.57%. Administration of E. camaldulensis extracts at doses of 100, 200, and 300 mg/kg significantly decreased parasitemia levels by 17.39, 61.88, and 60.53%, respectively (all P<0.05), relative to untreated control mice; however, standard antimalarial drugs were more efficacious and reduced parasitemia by 86.73%. Treatment with both E. camaldulensis extracts (100∼300 mg/kg) and standard antimalarial drugs significantly decreased malarial-induced physiological imbalances in liver and renal biomarkers, and serum electrolytes in malaria-infected mice compared with controls (P<0.05). The therapeutic effect of E. camaldulensis was greatest at a dose of 200 and 300 mg/kg. These findings indicate that E. camaldulensis aqueous leaf extracts could protect against malarial-induced aberrations in liver and renal function whilst exhibiting anti-malarial effects, and could explain its use as an antimalarial remedy in traditional medicine.

Antimalarial Activity of Tinospora baenzigeri against Plasmodium berghei-Infected Mice

Plant species of the genus Tinospora (Menispermaceae) possess several pharmacological properties, and T. crispa has been reported to have antimalarial activity. T. baenzigeri (Chingcha Chalee) is a rich source of terpenes and quinoline alkaloids; however, it still has not yet been investigated the antimalarial activity of this plant extract. Hence, this study was aimed to evaluate the antimalarial activity of T. baenzigeri stem extract against Plasmodium berghei-infected mice. The aqueous crude extract of T. baenzigeri stem was prepared using a microwave-assisted method and tested for acute toxicity in mice. For evaluating the antimalarial activity in vivo, the standard 4-day test was carried out using groups of ICR mice infected with P. berghei ANKA administered orally by gavage with the extract (100, 250, and 500 mg/kg) for 4 consecutive days. Parasitemia, body weight, packed cell volume, and mean survival time were then measured. It was found that the aqueous crude extract of T. baenzigeri stem did not exhibit any sign of toxicity up to the dose of 2,000 mg/kg. The extract significantly (P < 0.01) inhibited parasitemia in a dose-dependent manner, with 22.02%, 50.81%, and 74.95% inhibition. Moreover, the marked prevention of body weight loss and packed cell volume reduction was observed at doses of 100, 250, and 500 mg/kg of extract-treated mice. Additionally, the extract prolonged the mean survival time of P. berghei-infected mice, compared to the untreated group. In conclusion, the aqueous crude extract of T. baenzigeri stem has demonstrated potent antimalarial activity against P. berghei-infected mice with prolonged mean survival time and prevention of body weight loss and packed cell volume reduction.

Hypoglycemia induced by Plasmodium berghei infection is prevented by treatment with Tinospora crispa stem extract

During Plasmodium malaria parasite infection in a human, the intraerythrocytic stages lead to the clinical manifestations of the disease, especially hypoglycemia. Hypoglycemia is a recognized feature of severe malaria and linked with a high risk of mortality for children. Hence, the present study aimed to investigate the protective effect of T. crispa stem extract on hypoglycemia induced by P. berghei infection tested with a mouse model. ICR mice were inoculated with 1 × 10⁷ parasitized erythrocytes of P. berghei ANKA (PbANKA) by intraperitoneal injection and given 50, 100, and 200 mg/kg of ethanolic extract for 4-consecutive days. The results showed that T. crispa stem extract exerted a protective effect (100%) on hypoglycemia induced by PbANKA infection at doses of 100 and 200 mg/kg. A significantly (p < .05) prolonged mean survival time (28.0 ± 1.9 days) of the extract treated mice was also observed. Additionally, no effect on blood glucose levels was seen in normal mice treated with all doses of extract. It can be concluded that T. crispa stem extract may have beneficial properties in protecting against hypoglycemia, and in increasing survival time during malaria infection.

Antimalarial Properties of Aqueous Crude Extracts of Gynostemma pentaphyllum and Moringa oleifera Leaves in Combination with Artesunate in Plasmodium berghei-Infected Mice

Due to the emergence and spread of malaria parasite with resistance to antimalarial drugs, discovery and development of new, safe, and affordable antimalarial are urgently needed. In this respect, medicinal plant extracts are targets to optimize antimalarial actions and restore efficacy of standard antimalarial drugs. The present study was aimed at determining the antimalarial activities of Gynostemma pentaphyllum and Moringa oleifera leaf extracts in combination with artesunate against Plasmodium berghei-infected mice. P. berghei ANKA maintained by serial passage in ICR mice were used based on intraperitoneal injection of 1 × 10⁷ parasitized erythrocytes and subsequent development of parasitemia. These infected mice were used to investigate the antimalarial activity of artesunate (6 mg/kg) in combination with 500, 1,000, and 2,000 mg/kg of G. pentaphyllum and M. oleifera leaf extracts using 4-day suppressive test. It was found that these extracts showed significant (P < 0.05) antimalarial activity in dose-dependent manner with percentage of suppression of 45, 50, and 55% for G. pentaphyllum leaf extract and 35, 40, and 50% for M. oleifera leaf extract. Additionally, artesunate combined with these extracts presented higher antimalarial activity, compared to extract treated alone with percentage of suppression of 78, 91, and 96% for G. pentaphyllum leaf extract and 73, 82, and 91% for M. oleifera leaf extract. The results indicated that combination treatment of G. pentaphyllum or M. oleifera leaf extracts with artesunate was able to increase the antimalarial activity by using low dose of artesunate. Hence, these results justified the combination of these extracts and artesunate in antimalarial herbal remedies.