Microbes in Skin Probiotics: Difference between revisions

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== Nitrosomonas eutropha ==
== Nitrosomonas eutropha ==
== Bifidobacterium lactis ==
== Bifidobacterium lactis ==
''Bifidobacterium lactis'' is a gram-positive rod-shaped bacterium found in the large intestines of cows, cats, and humans. This bacteria was isolated from a breastfed infant in the 1980s. It is a subspecies deriving from ''Bifidobacterium animalis''. This bacterium was sequenced because of the boom of probiotic use and its possibility to be a good bacteria to add to the human gut microbiome. ''B. lactis'' is considered a good probiotic because it expresses fermentation activity,  it has a high aero tolerance and good stability. It can be found in formula, supplements, and fermented milk products globally. It also can go undetected orally because it does not have a taste or a specific texture that would make it a difficult consumable. It is able to survive the stressful environment of the gastrointestinal tract by having a high acid and bile salt tolerance. A specific strain of ''B. lactis'' named BB-12 expresses all of the main qualities of being a productive probiotic. It can inhibit pathogens, enhance barrier function, and aid in immune interactions (Jungerson et. al 2014).
Probiotics are able to interact with the immune system due to the interactions through the colonization of the gut mucosa and the gut-associated lymphatic tissue. Keeping the gut in a proper symbiotic environment reduces the event of gut dysbiosis that can lead to inflammatory events in other parts of the body including the GI tract. The metabolic processes of ''B. lactis'' can be attributed to the release of short-chain fatty acids (SCFA). Since ''B. lactis'' is a fermenter it can produce SCFAs as a byproduct of fiber breakdown. These SCFAs are used by the body and can decrease skin inflammation and other inflammatory processes due to their ability to influence macrophages, neutrophils, and other leukocytes. The ''Bifidobacteria'' family has also been known to help encourage the growth of immune cells like dendritic cells and T cells and are introduced early in life through breastfeeding. ''B. lactis'' and other organisms in this family have been able to decrease some inflammatory skin conditions as well as food allergies (Mann et al. 2020).
In a study to look at the use of probiotics to treat atopic dermatitis, commonly known as eczema, researchers  used ''B. lactis'' in association with a ''Lactobacillus'' strain. Their hypothesis was that a probiotic regimen of ''B. lactis'' and ''Lactobacillus casei'' would cause improvement in atopic dermatitis symptoms. A population of patients ranging from 4-17 years of age took the placebo or probiotic for 12 weeks. Following the 12-weeks the patients that received the probiotic had an increase in ''B. lactis'' found in their stool samples. When looking at this increase it lead to the belief that ''B. lactis'' has the ability to decrease the gut bacteria that typically will aggravate atopic dermatitis. The decrease in the bacteria aggravating AD and the increase in the ''B. lactis'' lead to a lower percentage of AD symptoms in these patients that received the probiotic course of treatment (Climent et. al 2021). This is a newer study and in the past opposing results have been found. Another study aimed at examining  AD in infants, found that Lactobacillus decreased AD flare-ups, but ''B. lactis'' had no overall effect. If there was an effect found it would not have been beneficial due to ''B. lactis'' being absent in stool samples when they were collected more than 3 days after probiotic ingestion (Wickens et al 2008).
In conclusion, a growing body of research shows evidence that  ''B. lactis'' helps to cultivate a healthy gut and stimulates down-regulation of inflammatory processes that are unnecessary in various systems in the body. It is able to establish a balanced gut microbiome and is a beneficial probiotic in some studies looking at atopic dermatitis. Due to its capability to communicate with the immune system and produce SCFAs it does serve as an aid to decrease inflammation which may translate to skin inflammation in the future.
== Lactobacillus rhamnosus ==
== Lactobacillus rhamnosus ==
== Lactobacillus acidophilus ==
== Lactobacillus acidophilus ==

Revision as of 03:43, 13 May 2022

Introduction

Review of Research on Skin Probiotic Microorganisms

Nitrosomonas eutropha

Bifidobacterium lactis

Bifidobacterium lactis is a gram-positive rod-shaped bacterium found in the large intestines of cows, cats, and humans. This bacteria was isolated from a breastfed infant in the 1980s. It is a subspecies deriving from Bifidobacterium animalis. This bacterium was sequenced because of the boom of probiotic use and its possibility to be a good bacteria to add to the human gut microbiome. B. lactis is considered a good probiotic because it expresses fermentation activity, it has a high aero tolerance and good stability. It can be found in formula, supplements, and fermented milk products globally. It also can go undetected orally because it does not have a taste or a specific texture that would make it a difficult consumable. It is able to survive the stressful environment of the gastrointestinal tract by having a high acid and bile salt tolerance. A specific strain of B. lactis named BB-12 expresses all of the main qualities of being a productive probiotic. It can inhibit pathogens, enhance barrier function, and aid in immune interactions (Jungerson et. al 2014). Probiotics are able to interact with the immune system due to the interactions through the colonization of the gut mucosa and the gut-associated lymphatic tissue. Keeping the gut in a proper symbiotic environment reduces the event of gut dysbiosis that can lead to inflammatory events in other parts of the body including the GI tract. The metabolic processes of B. lactis can be attributed to the release of short-chain fatty acids (SCFA). Since B. lactis is a fermenter it can produce SCFAs as a byproduct of fiber breakdown. These SCFAs are used by the body and can decrease skin inflammation and other inflammatory processes due to their ability to influence macrophages, neutrophils, and other leukocytes. The Bifidobacteria family has also been known to help encourage the growth of immune cells like dendritic cells and T cells and are introduced early in life through breastfeeding. B. lactis and other organisms in this family have been able to decrease some inflammatory skin conditions as well as food allergies (Mann et al. 2020). In a study to look at the use of probiotics to treat atopic dermatitis, commonly known as eczema, researchers used B. lactis in association with a Lactobacillus strain. Their hypothesis was that a probiotic regimen of B. lactis and Lactobacillus casei would cause improvement in atopic dermatitis symptoms. A population of patients ranging from 4-17 years of age took the placebo or probiotic for 12 weeks. Following the 12-weeks the patients that received the probiotic had an increase in B. lactis found in their stool samples. When looking at this increase it lead to the belief that B. lactis has the ability to decrease the gut bacteria that typically will aggravate atopic dermatitis. The decrease in the bacteria aggravating AD and the increase in the B. lactis lead to a lower percentage of AD symptoms in these patients that received the probiotic course of treatment (Climent et. al 2021). This is a newer study and in the past opposing results have been found. Another study aimed at examining AD in infants, found that Lactobacillus decreased AD flare-ups, but B. lactis had no overall effect. If there was an effect found it would not have been beneficial due to B. lactis being absent in stool samples when they were collected more than 3 days after probiotic ingestion (Wickens et al 2008). In conclusion, a growing body of research shows evidence that B. lactis helps to cultivate a healthy gut and stimulates down-regulation of inflammatory processes that are unnecessary in various systems in the body. It is able to establish a balanced gut microbiome and is a beneficial probiotic in some studies looking at atopic dermatitis. Due to its capability to communicate with the immune system and produce SCFAs it does serve as an aid to decrease inflammation which may translate to skin inflammation in the future.

Lactobacillus rhamnosus

Lactobacillus acidophilus

Lactobacillus acidophilus is a gram positive rod-shaped bacteria that is typically found in human and animal gastrointestinal tract and mouth (Badet and Thibauld, 2008). While more well known for its probiotic uses in dairy products such as yogurt, L. acidophilus has been recently receiving attention for its uses in skin care as an anti-wrinkle agent.

L. acidophilus was first noticed for potential skin treatments alongside the proposed gut-brain-skin theory by John H. Stokes and Donald M. Pillsbury around the 1930s. The theory proposed that gastrointestinal microbiome and function were tied to mental health disorders and skin conditions such as acne. Chronic emotional states alter the gastrointestinal tract, which disturb the intestinal microbial flora and increase the risk for intestinal permeability. The resulting impact is an increase in inflammation to the skin. The proposed solution was 'the direct introduction of acidophil organisms in cultures,' which could be distributed with tablets or drinks. Formal studies were conducted starting in the 1960s, often with oral probiotic tablets containing L. acidophilus in combination with other bacteria such as L. bulgaricus and B. bifidum. While flawed, these studies indicated a strong correlation between the intake of bacteria and the reduction of inflammation acne and other skin lesions (Bowe WP et. al. 2011).

More recent studies have turned their focus on tyndalized L. acidophilus's effects on UV damaged skin as an anti-wrinkle agent. A study in 2016 focused on UVB radiation on the skin of hairless mice and the potential effects from orally administered tyndalized L. acidophilus tablets. Tyndallization is an outdated sterilization process that heats a solution at or just below boiling temperatures, and is used today to kill bacteria as well as any endospores possibly contained inside. The mice exposed to UVB rays experienced significant skin dehydration and transepidermal water loss, however thanks to frequent ingesting L. acidophilus beforehand, some of the hydration and water retention was retained in the skin and the overall damage was not as severe. Skin samples also revealed a more even collagen distribution among mice that received the L. acidophilus tablets, resulting in a lower level of wrinkling as a result of UV irradiation. A western blot has revealed that the MMPs, specifically MMP-1 and MMP-9, alongside signaling parts involved in the p38 MAPK pathway, have a reduced expression. These enzymes are strongly expressed as a result of UV irradiation, so further investigation on how L. acidophilus reduces the expression could be explored (Im AR et al. 2016).

Further studies have explored L. acidophilus effects on human cells alongside mice cells. Human keratinocytes and human dermal fibroblast cells were exposed to UVB irradiation to observe the skin's biological response to tyndallized L. acidophilus, specifically L. acidophilus-KCCM12625P. The cell viability of HaCaT and HDF cells saw a recovery from ROS generation due to UVB irradiation after exposure to L. acidophilus, indicating antioxidant effects. ROS induced wrinkles as a result of induction of MMPs and elastase enzymes were also inhibited in a dose-dependent manner. The melanogenesis of B16F10 mice cells through UVB irradiation was also observed, and indicated that L. acidophilus does not directly affect tyrosinase activity but has anti-melanogenesis effects through regulation of cAMP signaling pathways (Lim HY et. al. 2020).

The overarching conclusion is that L. acidophilus does have potential positive benefits to skin care, with a particular emphasis on skin protection from UVB irradiation damages. L. acidophilus has been found to aid in the reduction of dehydration, water retention, and inhibiting ROS induced wrinkles from mice models. This is achieved through impacting the p38 MAPK and cAMP pathways. Human cell culture models also saw a recovery from ROS induced wrinkles through the known molecular "aging" markers. However, studies using human subjects are either lacking or flawed. The early studies often either did not have a control for comparison, or were difficult to evaluate due to different language or accessibility. Nevertheless, these findings provide a solid basis for future analysis on L. acidophilus's role in skin care.

Lactobacillus paracasei

Conclusion

References