Evidence of Immunosuppressive and Th2 Immune Polarizing Effects of Antidiabetic Momordica charantia Fruit Juice

Abstract

The mechanism of action of the antidiabetic capacity of Momordica charantia is still under investigation. Here, we assessed phytochemical compositions, antioxidant activity, and effects of total and filtered fruit and leafy stem juices of Momordica charantia on human T cell proliferation and differentiation through quantification of Th1/Th2 cytokines. In the absence of stimulation, total fruit and leafy stem juices induced significant T cell proliferation. Under PHA stimulation, both juices potentiated plant-induced T cell proliferation. However, the filtered fruit and leafy stem juices significantly inhibited PHA-stimulated T cell proliferation, while neither juice influenced T cell proliferation. Moreover, total and filtered fruit juice increased IL-4 secretion, while total and filtered leafy stem juice enhanced IFN-γ production. Phytochemical screening revealed the presence of tannins, flavonoids, anthocyans, steroids, and triterpenoids in both juices. Alkaloids, quinone derivatives, cardenolides, and cyanogenic derivatives were undetectable. The saponins present in total juices were undetectable after filtration. Moreover, both juices had appreciable antioxidant capacity. Our study supports the type 1 antidiabetic effect of filtered fruit juice of M. charantia which may be related to its immunosuppressive and T-helper 2 cell inducing capacities. Due to their immune-stimulatory activities and their ability to increase T-helper 1 cell cytokines, total fruit and leafy stem juices may serve in the treatment of immunodeficiency and certain infections.

Effectiveness of Antihyperglycemic Effect of Momordica charantia: Implication of T‐Cell Cytokines

“…M. charantia fruit juice was prepared as we have previously described [ 2 ]. Briefly, 100 g of fresh fruits were manually ground and pressed with 100 ml of sterilized distilled water to obtain fruit juice according to slightly modified methods of Raza et al [ 8 ].…”

“…For our contribution, we have previously undertaken studies and demonstrated the antihyperglycemic effects of three African medicinal plants in diabetic pregnancy in rats [ 1 ]. Very recently, we have also shown the immune-modulatory effect of Momordica (M.) charantia [ 2 ], a plant commonly used in Africa and south Asia for diabetes treatment. During several decades, M. charantia is one of the plants which have gained most attention from several researchers [ 2 – 10 ].…”

“…Very recently, we have also shown the immune-modulatory effect of Momordica (M.) charantia [ 2 ], a plant commonly used in Africa and south Asia for diabetes treatment. During several decades, M. charantia is one of the plants which have gained most attention from several researchers [ 2 – 10 ]. M. charantia also called “bitter melon” or African cucumber is a plant of Cucurbitaceae family widely cultivated in tropical and subtropical regions and is commonly used in Mediterranean traditional medicine for its antidiabetic properties and antihyperglycemic, antitumor, anti-inflammatory, and cytotoxic activities [ 3 – 9 ].…”

“…As mentioned above, we have found in our very recent study that the filtered M charantia fruit juice (saponins-depleted fruit juice) elicited immunosuppressive and Th2-inducing phenotype on human T-lymphocytes in vitro [ 2 ], suggesting that M. charantia fruit juice could have beneficial effect in autoimmune type 1 diabetes. Thus, we were prompted to investigate the effect of such juice in vivo in STZ-induced diabetic rats.…”

Modulatory effects of Momordica balsamina on Th1/Th2 cytokine profiles in immune-challenged rats

“…The immunostimulatory effects of other Momordica species have been coincidentally described by a number of in vitro and in vivo studies. Leafy stem juices of M. charantia induced significant T cell proliferation and enhanced IFN-γ production (Fachinan et al, 2017). Augmented cell-mediated and antibody-mediated immunity evident by increased Delayed Type Hypersensitivity (DTH) and Haemagglutinating Antibody Titre (HAT), respectively, was observed after oral administration of Momordica charantia to immunized rats (Prasad et al, 2010).…”