Potentials of Immunonutrition in Wound Healing: A Review (Potensi Imunonutrisi dalam Penyembuhan Luka: Tinjauan) / Jurnal Sains Kesihatan Malaysia

@#A delayed wound healing process can lead to detrimental complications in chronic wound patients such as tissue necrosis and systemic infections. Application of immunonutrition (IN) in experimental animal models and chronic wound patients has shown promising and improved wound healing processes. IN restores the supply of essential nutrients that are critical for cell growth and tissue repair in the wounded subjects. Several commonly found nutrients in IN formulations include polyunsaturated fatty acids (PUFAs), essential amino acids, trace elements such as zinc and vitamins. Recently, some studies suggested the use of traditionally used herbs like curcumin in IN recipes due to its efficient wound healing properties. The roles and functions of IN in wound healing encompass recruitment of white blood cells, platelets and fibroblasts into the wounded area during the coagulation and inflammation phases, enhancement of fibroblast proliferation, collagen synthesis and neovascularization in the proliferation phase; and lastly, regulation of tissue re-epithelization for wound closure and recovery. In this review, the roles and functions of individual nutrients were deliberately discussed alongside their mechanisms of action in wound healing. This aims to provide a more holistic insight into the potentials of those nutrients when used as part of IN for major wound patients. Despite its remarkable effects in wound healing, several criteria should be considered in an IN formulation: the type and severity of wounds, administration timing and mode of administration, and concoction of immune-boosting nutrients in order to ensure the optimal wound healing effects.

Multi-Epitope Peptide-Based and VacciniaBased Universal Influenza Vaccine Candidates Subjected to Clinical Trials

@#In light of the limited protection conferred by current influenza vaccines, immunisation using universal influenza vaccines has been proposed for protection against all or most influenza sub-types. The fundamental principle of universal influenza vaccines is based on conserved antigens found in most influenza strains, such as matrix 2, nucleocapsid, matrix 1 and stem of hemagglutinin proteins. These antigens trigger cross-protective immunity against different influenza strains. Many researchers have attempted to produce the conserved epitopes of these antigens in the form of peptides in the hope of generating universal influenza vaccine candidates that can broadly induce cross-reactive protection against influenza viral infections. However, peptide vaccines are poorly immunogenic when applied individually owing to their small molecular sizes. Hence, strategies, such as combining peptides as multi-epitope vaccines or presenting peptides on vaccinia virus particles, are employed. This review discusses the clinical and laboratory findings of several multi-epitope peptide vaccine candidates and vaccinia-based peptide vaccines. The majority of these vaccine candidates have reached the clinical trial phase. The findings in this study will indeed shed light on the applicability of universal influenza vaccines to prevent seasonal and pandemic influenza outbreaks in the near future.

Endophytic fungi from Maliau Basin, Sabah: Identification of strains and antimicrobial compounds

Aims@#Endophytic fungi are microorganisms that live asymptomatically within plant tissues, producing a wide range of metabolites, including compounds potentially useful for drug development. We investigated endophytic fungi from Maliau Basin, Sabah to identify strains producing bioactive compounds, notably with antimicrobial activity. @*Methodology and results@#A total of 23 plants were sampled yielding 345 endophytic fungal isolates. Of these, 44 isolates were screened for antimicrobial activity against nine species of bacteria and fungi, revealing 14 endophytes producing bioactive metabolites. Crude fungal extracts were obtained from broth cultures of endophytic isolates with promising activity while the fungal strains were identified using molecular methods. The crude extract of endophyte MB4 WA10, isolated from Callophyllum sp. (bintangor) showed IC50 of 2.6 mg/mL against S. aureus and 0.6 mg/mL against B. subtilis while the extract of MB22 WA16, an isolate identified as Valsaceae sp., was also active against S. aureus with an IC50 of 1.37 mg/mL. Another isolate, namely MB5 L4 (WA), was identified as a Phomopsis sp. and its extract was the most active against S. aureus with an IC50 of 1 mg/mL. The HPLC fraction of this fungal extract with the highest inhibition (92.37%) of S. aureus was purified for compound isolation and identification. A polyketide compound, 2,3-dihydro-2- hydroxy-2,4-dimethyl-5-trans-propenylfuran-3-one (C9H12O3), with molecular weight of 168.192 was identified based on mass spectral and NMR data analysis. This previously identified compound is known to have other antimicrobial properties. @*Conclusion, significance and impact of study@#Rainforests in Malaysia, especially Maliau Basin, harbour many species of fungal endophytes, producing useful bioactive compounds that may be explored for further potential uses, including antimicrobial activity.

Lactobacillus casei strain C1 attenuates vascular changes in spontaneously hypertensive rats

Hypertension can be caused by various factors while the predominant causes include increase in body fluid volume and resistance in the circulatory system that elevate the blood pressure. Consumption of probiotics has been proven to attenuate hypertension; however, the effect is much strain-dependent. In this study, a newly isolated Lactobacillus casei (Lb. casei) strain C1 was investigated for its antihypertensive properties in spontaneously hypertensive rats (SHR). Lactic acid bacteria (LAB) suspension of 11 log colony-forming unit (CFU) was given to SHR (SHR+LAB, n=8), and phosphate buffer saline (PBS) was given as a control in SHR (SHR, n=8) and in Wistar rats as sham (WIS, n=8). The treatment was given via oral gavage for 8 weeks. The results showed that the weekly systolic blood pressure (SBP), mean arterial pressure (MAP), diastolic blood pressure (DBP) and aortic reactivity function were remarkably improved after 8 weeks of bacterial administration in SHR+LAB. These effects were mostly attributed by restoration of wall tension and tensile stress following the bacterial treatment. Although not statistically significant, the level of malondialdehye (MDA) in SHR+LAB serum was found declining. Increased levels of glutathione (GSH) and nitric oxide (NO) in SHR+LAB serum suggested that the bacterium exerted vascular protection through antioxidative functions and relatively high NO level that induced vasodilation. Collectively, Lb. casei strain C1 is a promising alternative for hypertension improvement.

Identification and Characterization of Lactic Acid Bacteria (LAB) Isolated from Probiotic Drinks in Malaysia / Jurnal Sains Kesihatan Malaysia

Many studies have shown that probiotic strains added to a number of probiotic products are not compatible to that of claimed. It is thus of note to validate probiotic strains added to probiotic products. In this study, three probiotic drinks, A, B and C, were cultured on MRS agar and the number of bacterial colonies was enumerated. The bacterial counts recovered from A (9.3 ± 6.9 log CFU/ml) and C (9.0 ± 6.9 log CFU/ml) were signifi cantly higher than B (5.2 ± 3.5 log CFU/ml) and achieved the minimal amount recommended for probiotic bacteria. All of the isolates appeared as gram positive rods microscopically and were proven to be catalase negative. However, there were only A1, A2, B4 and C1 that were highly tolerant to the gastrointestinal pH 3 to 6. The four isolates produced and secreted antimicrobial substances which inhibited the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). C1 showed the greatest growth inhibition by forming 17.50-mm and 17.85-mm inhibition zones against E. coli and S. aureus, respectively. The 16s rDNA sequencing and phylogenetic analysis were performed to further identify the twelve isolates. The twelve isolates were found to be Lactobacillus (L.), particularly L. casei and L. paracasei. However, the bacteria isolated from drink B were incompatible to the labelled ones. In conclusion, probiotic drinks are possible to contain different bacterial counts and probiotic strains from the labelled ones. These differences might affect health benefi ts rendered by probiotic strains to consumers.