Volatile fatty acids production in ruminants and the role of monocarboxylate transporters: A review

Monocarboxylates commonly referred to as short-chain fatty acids (SCFAs) are metabolized to different extents by the epithelium of the gastrointestinal tract. They are absorbed along different segments of the gastrointestinal tract and constitute a significant amount of energy in ruminants. Monocarboxylates play a central role in cellular metabolism and metabolic communication between tissues. Essential to these roles is their rapid transport across the plasma membrane, which is catalyzed by a recently identified family of proton-linked monocarboxylate transporters (MCTs). Monocarboxylate transporter-1 and 4 have been shown to interact specifically with OX-47 (CD147), a member of the immunoglobulin superfamily with a single transmembrane helix. This interaction appears to assist MCT expression at the cell surface. Despite the importance of short-chain fatty acids in being the main energy source in ruminant animals, the mechanism of SCFAs transport and absorption is still not fully studied. The aim of this review is to critically discuss short-chain fatty acids production and the functional role of monocarboxylate transporters in relation to the transport and absorption of these nutrients along the gastrointestinal tract of ruminants. Two major functions of monocarboxylate transporter proteins, namely the facilitation of the absorption of SCFAs in the gastrointestinal tract and the regulation of cell pH in skeletal muscles, are clearly very important for physiological homeostasis, animal welfare and productivity.Key words: Ruminants, monocarboxylates, monocarboxylate transporters, CD147

Effect of fraction iv portion of Ximenia americana stem bark on Trypanosoma congolense - induced serum enzymes changes in rats

The current study investigates the effect of fraction IV portion of Ximenia americana stem bark on Trypanosoma congolense induced serum enzymes changes in rats. Following infection with trypanosomes, the rats were monitored for levels of some serum enzymes. The results revealed that there was significant (P<0.05) elevation of serum enzymes Aspartate AminoTransferase (AST), Alanine AminoTransferase (ALT), Alkaline Phosphatase (AP), Gamma GlutamylTransferase (GGT) and Creatine Kinase (CK) in the infected animals. Treatment with 25 mg/Kg body weight fraction IV portion of Ximenia americana led to significant (P<0.05) reduction in levels of the enzymes. It is concluded that treatment with fraction IV portion of Ximenia americana was able to modulate the effect of trypanosomosis induced serum enzyme levels of the infected rats.Key words: Fraction IV, serum enzymes, Trypanosoma congolense, Ximenia american

Antioxidant properties of Ximenia americana

Ximenia americana, a medicinal plant, was evaluated for free radical scavenging and antioxidant activity. The extracts from the stem bark was obtained using methanol. The methanol portion was again fractionated into flavonoid and saponnin portions. The antioxidant activity of the portions was assessed by the 2, 2 diphenyl-1-picryl-hydrazyl (DPPH) assay. The flavonoid portion revealed a significant (P < 0.05) antioxidant activity with the Rc50 value of 8. The study reveals that X. americana could be used as a potential antioxidant.Key words: Ximenia americana, flavonoid, antioxidant activity

Acute toxicity studies of aqueous stem bark extract of Ximenia americana

Increasing interest in medicinal plants has increased scientific scrutiny of their therapeutic potentials and safety thereby providing physicians with data to help patients make wise decision on their usage.The stem bark of Ximenia americana was evaluated for its phytochemical constituents and acute toxicity effect on thirty Swiss albino mice. The extracts were administered intraperitoneally/orally atdoses of 10, 100, and 1000 mg/kg body weight. The results revealed no death with doses up to 5000 mg/kg body weight. However, the initial reactions included excitement, restlessness, lack of appetiteand later reduced activity during the first 24 h of extract administration. The symptoms were dose dependent with signs noticeable with increasing dosage. Post mortem, hematological and histopathological examination did not show any significant (