Nutrition for Dermal Therapies

Question: Discuss about the Nutrition for Dermal Therapies. Answer: Introduction: Wound healing is a complex process and leads to restore tissue damage. Amino acid arginine plays significant role in this restoration of tissue damage. Arginine proved to be effective in improving wounf healing, increasing collagen deposition and decreasing breaking strength of incisions. Hence, arginine proved to be effective in wound healing. Arginine is an essential amino acid which is a part of urea cycle. Arginine is intraconvertible to citrulline, ornithine, and agmatine. In a healthy human, 2 g per day arginine can be synthesized by the kidney from citrulline. Citrulline can be converted to arginine by action of series of enzymes like argininosuccinate synthetase and argininosuccinate lyase. Biosynthetic pathways cant prepare sufficient amount of arginine based on the condition of the individual. It should be supplemented externally in young people and in few cases like injury and burns (Currell and Dam-Mieras, 2014). Persons with poor nutrition should be advised to consume foods containing arginine. Arginine can be obtained from both plant and animal sources. Animals sources of arginine comprises of dairy products like cottage cheese, ricotta, milk, yogurt and whey protein drinks, beef and pork like gelatin and chicken, and turkey light meat, seafood like halibut, lobster, salmon, shrimp, snails and tuna. Plant sour ces of arginine comprises of wheat germ and flour, lupins, buckwheat, granola, oatmeal, peanuts, nuts like coconut, pecans, cashews, walnuts, almonds, Brazil nuts, hazelnuts and, pinenuts, seeds like hemp, pumpkin, sesame and sunflower, chickpeas, cooked soybeans and Phalaris canariensis (Patel et al., 2016). Wound healing is a multifaceted and dynamic process. In wound healing, there is replacement of devitalized and missing cellular structures and tissue layers. Wound healing includes four phases like hemostasis phase, the inflammatory phase, the proliferation phase, and the remodeling phase (Demidova-Rice et al., 2012). Hemostasis phase occurs in the first few minutes after injury. Platelets stick to injured site and platelets get activated. Platelets change to the amorphous shape and release factors responsible for clotting. As a result, there is activation of fibrin and formation of mesh which facilitate binding of platelets to each other. This clot formation plugs broken part of blood vessels and prevents further bleeding. In inflammatory phase, there is clearance of damaged cells, dead cells, bacteria, other pathogens and debris. In proliferation phase, there is occurrence of angiogenesis, collagen deposition, granulation tissue formation, epithelialization, and wound contraction. In remodeling phase, collagen realigned in line with the tension lines and unwanted cells gets removed by apoptosis (Singh et al., 2013) Wound healing comprises of different events like chemotaxis, phagocytosis, angiogenesis, production of new glycosaminoglycans and proteoglycans, neocollagenesis, collagen degradation, epithelization, and collagen remodeling. In wound healing there is replacement of normal skin with the fibroblastic mediated scar tissue. In normal skin, epidermis and dermis form a protective barrier against external stimuli. When this barrier is disrupted, a series of biochemical reactions occur to repair the damage. Wound healing process is fragile process and its interruption and failure in this process can lead to chronic wounds. Non-healing wounds mainly occur in patients of diabetes mellitus, cardiovascular disease, infection and metabolic deficiencies due to old age. In such cases treatment and management should be provided to the patient. One of the management approaches for wound healing is by supplementation of the nutrients like arginine because nutritional deficiencies have significant impa ct on the wound healing (Demidova-Rice et al., 2012) Cellular mechanisms: Arginine can synthesize highly reactive nitric oxide (NO), which releases citrulline. This citrulline can be recycled to arginine. Administration of arginine can be useful in improving blood flow to the limbs in both normal and diseased individuals. Arginine potentiates release of growth factor and insulin-like growth factor I (IGF-1), both of which are responsible for improvement in the wound healing. Animals exhibited improvement in survival rate, increased wound-breaking strength and augmented wound collagen accumulation. Arginine produces its effects in wound by two pathways like NOS isoforms and arginase isoforms. It is evident that there are increased levels of citrulline and NOx in wound as compared to plasma. It indicates NOS is responsible for conversion of arginine. There are more levels of ornithine in wound as compared to the plasma. It indicates arginase is responsible for arginine metabolism. There is temporal increase in citrulline and NOx levels in wound, indicating s equential stimulation of different arginine metabolic pathways at the wound site. NOx dependent pathway is responsible for the initial phase of wound healing while citrulline dependent pathway is responsible for the later phase of wound healing. There is increased iNOS expression in macrophages, PMNs, fibroblasts, epithelial and endothelial cells in skin at wound site as compared to the skin at normal site (Chow and Barbu, 2014). Arginine is necessary for NO synthesis by activated macrophages and neutrophils. Arginine facilitate fibroblast formation which is essential for collagen formation and tissue repair. In vitro and in vivo studies indicate that collagen synthesis in wound fibroblasts is regulated by NO. In vitro studies indicate that stimulation of human fibroblsts from skin with LPS and INF-gamma produces more amount of eNOS and iNOS. It indicates increase in inflammatory cytokines in wound. It is evident that arginine can inhibit inflammatory cytokines like TNF-alpha and IN F- gamma. There is increased expression of ARG1 and ARG2 in PMN in skin of wound, while there is no expression in skin without wound. In vitro studies indicate that function of arginase release form the PMN is to reduce NO formation by macrophages, endothelial cells and T cells. However, this fact should be proved in vivo studies by conducting more number of studies. Upregulation of ARG1 in wound fibroblasts provides substrate for collagen synthesis and cell proliferation. It is evident that ARG1 is necessary for ornithine production and ARG2 for polyamines production in bovine endothelial cells. It indicates that both the pathways are important for the wound healing process (Kurmis et al., 2010). Inducible nitric oxide synthase (iNOS) production increases and peaks within 24 72 hours after wound and it leads to the NO and citrulline production. NO exhibits its action by acting as antimicrobial agents and by augmenting blood flow to the healing wound. Transforming growth factor- (TGF-) which is an inhibitor of iNOS pathway can stimulate arginase pathway and production of collagen. In the final step of the urea cycle, arginase acts as catalyst to break arginine into ornithine and urea. There are two isoforms of arginase are available like arginase 1 and arginase 2. Both of these isoforms can play important role in would healing by increasing production of ornithine. This ornithine can be metabolized to numerous polyamines under the action of ornithine decarboxylase. These polyamines facilitate cellular growth, required for the wound healing. Arginine is also important for the stimulation of vascular endothelial growth factor (VEGF) and keratinocyte growth factor. Arginine is u seful in healing of cutaneous wounds and also useful in healing of fractures. Arginine is also useful in treating wounds due to different clinical conditions like diabetes and hemorrhage/trauma. It has been observed that arginase levels are less in wound as compared to the plasma. It indicates arginine consumption at wound site. Both growth hormone and NO are responsible for the wound healing by arginine supplementation because arginine did not exhibit improvement in wound healing breakage strength and/or collagen deposition in iNOS KO mice. It is evident from the literature that arginine can increase protein amount in wounds and muscles by a different mechanism from NO production (Singh et al., 2012; Debats et al., 2011). Measured outcomes in treating wound with arginine comprises of different physical and biochemical parameters. These outcomes comprises of rate of healing, elevation of insulin growth factor 1, improved nitrogen balance, increased hydroxyprolyne accumulation which indicates collage deposition, rate of epithalization of wounds, increased response of lymphocytes to mitogenic and allogeneic stimulation (Alexander and Dorothy, 2014). Role of arginine in wound healing can be established by measuring biomarkers in both plasma and wounds. These biomarkers include arginase-1, arginase-2, NOx, iNOS and eNOS. Expression of these markers can be measured in different cells like epithelial cells, fibroblasts, polymorphonuclear (PMNs) cells, macrophages, endothelial cells and glandular cells. There is increase in the level of these markers in wounded skin as compared to the unwounded skin. NOx, iNOS and eNOS levels in the plasma and wound can be measured using HPLC. Arginase levels can be measure u sing ELISA method and western blot technique. Cellular distribution of these markers can be detected using Immunohistochemical staining (Drover et al., 2014). It is evident that, 20 g/day arginine can be safely administered to adults and it is well tolerated in adults. However, there was no significant study done to establish dose response curve of arginine, most effective dose and timing of administration. Arginine is safe when consumed in the prescribed dose. However, it can produce adverse effects when consumed in the excess dose. These adverse effects include abdominal pain, bloating, diarrhea, gout, and blood abnormalities. Arginine should be administered in the children with more caution because high dose of arginine can produce serious adverse effects including death in children. It is evident that arginine can multiply herpes virus. Hence, arginine can make herpes worse. In patients with low blood pressure Arginine should be administered with caution because arginine can reduce blood pressure. As arginine has effect on blood pressure, it should not be taken before and after 2 weeks of surgery. Arginine can increase risk of death af ter heart attack in older people. Hence, it should not be taken immedietly after heart attack. In patients with kidney disease, arginine can increase potassium levels, increasing risk of irregular heart beat. Arginine has the property of producing allergic reactions. Hence, it should be taken with caution in Asthma patients. Anaphylaxis and hives are also reported in persons with arginine consumption. Arginine may increase risk of bleeding, hence it should not be taken with medications which increases risk of bleeding. High doses of arginine should not be administerd in patients with established sepsis because it can cause hypotension and other cardiovascular complications (Kotsirilos et al., 2011; Patel et al., 2016). There is abundant literature from animal studies and clinical trials available for the usefulness of arginine in wound healing. Seifter and collegues showed that arginine deficient animals, when supplemented with arginine exhibited increased wound collage deposition, augumented wound breaking strength and increased survival. In an animal study, Zhang and collegues reported that there was increased protein balance in skin wound and muscles. Leigh and collegues conducted a study on humans with the administration of 4.5 g and 9 gm twice daily for three weeks in patients with pressure ulcers. At both the administered doses healing rate was similar, however, healing rate was improved in treatment groups as compared to the control group. In one study administration of 17 g arginine for 14 days resulted in significant increase in IGF-1 and improved nitrogen balance compared to placebo group. In another study with 17 gm arginine for 14 days, treatment group exhibited enhanced hydroxyprolene accumulation which indicates augumented collagen production and elevated levels of IGF-1, however, there was no change in the rate of epithelialization of the wound. A comprehensive study was conducted by De Luis, comprising of 72 patients and arginine supplementation was initiated after 24 hours after surgery. In this study, it was observed that fistula formation and length of stay in the hospital were less as compared to the control group (Alexander and Dorothy, 2014). Conclusion: Until recently, primary focus of nutrients is to prevent nutritional deficiencies. However, in recent times nutrients are increasingly proved to be efficacious in the treatment of disease conditions. Arginine is an amino acid useful in the wound healing. Translational and clinical data are available for the wound healing properties of the arginine. It has been established that arginine can exhibit wound healing property through NO pathway and arginase pathway. Arginine is also safe when consumed in the prescribed dose. Energy and protein requirements should be met while administering arginine for wound healing. In summary, arginine administration can improve wound healing. References: Alexander, J. W., and Dorothy, M. (2014). Role of Arginine and Omega-3 Fatty Acids in Wound Healing and Infection. Advances in Wound Care, 3(11), 682690. Chow, O., and Barbu, A. (2014). Immunonutrition: Role in Wound Healing and Tissue Regeneration. Advances in Wound Care, 3(1), 4653. Currell, B.C., and Dam-Mieras, R.C.E. (2014). Biosynthesis Integration of Cell Metabolism. Butterworth-Heinemann. Debats, I.B., Koeneman, M.M., Booi, D.I., Bekers, O., and van der Hulst, R.R. (2011). Intravenous arginine and human skin graft donor site healing: a randomized controlled trial. Burns, 37, 420. Demidova-Rice, T. N., Hamblin, M. R., and Herman, I. M. (2012). Acute and Impaired Wound Healing: Pathophysiology and Current Methods for Drug Delivery, Part 1: Normal and Chronic Wounds: Biology, Causes, and Approaches to Care. Advances in Skin Wound Care, 25(7), 304314. Demidova-Rice, T. N., Hamblin, M. R., and Herman, I. M. (2012). Acute and impaired wound healing: pathophysiology and current methods for drug delivery, part 2: role of growth factors in normal and pathological wound healing: therapeutic potential and methods of delivery. Advances in Skin Wound Care, 25(8), 349-70. Drover, J.W., Dhaliwal, R., Weitzel, L., Wischmeyer, P.E., Ochoa, J.B., and Heyland, D.K. (2011). Perioperative use of arginine-supplemented diets: a systematic review of the evidence. Journal of the American College of Surgeons, 212, 385. Kotsirilos, V., Vitetta, L., and Sali, A. (2011). A Guide to Evidence-based Integrative and Complementary Medicine. Elsevier Australia. Kurmis, R., Parker, A., Greenwood, J. (2010). The use of immunonutrition in burn injury care: where are we? Journal of Burn Care Research, 31(5), 677-91. Patel, V. B., Preedy, V. R., and Rajendram, R. (2016). L-Arginine in Clinical Nutrition. Humana Press. Singh, M.R., Saraf, S., Vyas, A., Jain, V., and Singh, D. (2013). Innovative approaches in wound healing: trajectory and advances. Artificial Cells, Nanomedicine, and Biotechnology, 41(3), 202-12. Singh, K., Coburn, L.A., Barry, D.P., Boucher, J., Chaturvedi, R., and Wilson, K.T. (2012). L-arginine uptake by cationic amino acid transporter 2 is essential for colonic epithelial cell restitution. American Journal of Physiology-Gastrointestinal and Liver Physiology, 302, G1061.