Aloe Preparations Research Articles

Decolorized Aloe vera polysaccharide enriched preparations and their effects on human gastrointestinal cell lines

Introduction: Aloe vera (A. vera) has been used as a folk remedy to treat different gastrointestinal and metabolic symptoms as well as for traditional therapeutic and topical cosmetic uses.It has been proposed that its benefits are based on aloe´s unique composition of phytochemicals, in particular the complex polysaccharides that are present in the gel. Commercial A. vera juice is purified to remove latex constituents (such as anthraquinones) via activated charcoal filtration (decolorization). Limited information is available regarding A. vera’s biological effects after decolorization on the gastrointestinal tract. Objective: To evaluate the effect of different polysaccharide-enriched decolorized preparations of A. vera (whole leaf -WL- or inner leaf -InL-) on two human cells lines: stomach gastric adenocarcinoma (AGS) and Intestinal Myofibroblast (InMyoFib) cells. We hypothesize that these enriched preparations will have beneficial effects in these gut cell models. M&M: Proliferation: Cell Proliferation Kit I (MTS, Cat. No: 11465007001-Roche-SIGMA-ALDRICH).Scratch studies: Quantification was carried out using ImageJ software (NIH, Bethesda, MD).Apoptosis: H2O2 and Cytokine mix-induced apoptosis was analyzed using cell death detection ELISA plus (Sigma Cat. No 11 774 425 001; Roche Cat. No 11 544 675 001).Statistics: ANOVA, repeated measured design. 5 independent experiments. Results: 6 different preparations were tested at 3 concentrations: 10, 50 and 100 ug/ml in all the experiments. Proliferation: None of the preparations induced cell proliferation in AGS and Inmyofib cells.; 2 InL and 1 WL preparation inhibited AGS and Inmyofib cell proliferation in comparation to the negative control. Wound healing: A significant improvement was induced by all fractions tested in both cell types. Preparations improved the percentage of wound healing in comparation with the negative control, one WL improved this parameter to levels similar to the positive control. Apoptosis: Four out of the six extracts protected cells from H2O2-induced apoptosis in both cell lines. In the case of the cytokine stimulation, AGS cells evoked a 55% increase over the negative control. None of the herbal extracts could revert/prevent apoptosis in this cell line. Conversely, cytokines evoked an 80% increase in apoptosis in Inmyofyb cells and Aloe preparations were largely effective in inhibiting this process. Conclusion: It has been proposed that A. vera gel has the ability to treat or protect gastric ulcers and to alleviate intestinal discomfort in both in animals and humans. These activities have been attributed to several possible mechanisms, including its anti-inflammatory properties, healing effects, mucus-stimulatory effects and regulation of gastric secretions. Here we show that decolorized A. vera polysaccharide-enriched preparations can modulate gastrointestinal cell lines. Conflict of Interest Disclosure: This work was funded by Herbalife Nutrition International of America, Inc. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Aloe vera: A review of toxicity and adverse clinical effects

ABSTRACTThe Aloe plant is employed as a dietary supplement in a variety of foods and as an ingredient in cosmetic products. The widespread human exposure and its potential toxic and carcinogenic activities raise safety concerns. Chemical analysis reveals that the Aloe plant contains various polysaccharides and phenolic chemicals, notably anthraquinones. Ingestion of Aloe preparations is associated with diarrhea, hypokalemia, pseudomelanosis coli, kidney failure, as well as phototoxicity and hypersensitive reactions. Recently, Aloe vera whole leaf extract showed clear evidence of carcinogenic activity in rats, and was classified by the International Agency for Research on Cancer as a possible human carcinogen (Group 2B). This review presents updated information on the toxicological effects, including the cytotoxicity, genotoxicity, carcinogenicity, and adverse clinical effects of Aloe vera whole leaf extract, gel, and latex.

Meeting Report: First National Meeting on Aloe, April 20–21, 2013, Isernia, Italy New Perspectives in Aloe Research: From Basic Science to Clinical Application

Aloe preparations have maintaining their popularity over the of course time. Aloe latex is used for its laxative effects; aloe gel is used topically for skin ailments and internally for variety of disturbances; aloe extract is potentially useful for cancer.

Effects ofAloe veraSupplementation in Subjects with Prediabetes/Metabolic Syndrome

Metabolic syndrome affects 1 in 3 U.S. adults. The primary target of treatment of patients with metabolic syndrome is therapeutic lifestyle change. Numerous animal trials have reported positive effects of Aloe vera in in vivo models of diabetes, but there is a paucity of controlled clinical trials in patients with prediabetes. Thus, the objective of this pilot study was to examine the effect of aloe compared to placebo on fasting blood glucose, lipid profile, and oxidative stress in subjects with prediabetes/metabolic syndrome. This was a double-blind, placebo-controlled Institutional Review Board (IRB)-approved pilot study of two aloe products (UP780 and AC952) in patients with prediabetes over an 8-week period. A total of 45 subjects with impaired fasting glucose or impaired glucose tolerance and having two other features of metabolic syndrome were recruited (n=15/group). Parameters of glycemia [fasting glucose, insulin, homeostasis model assessment (HOMA), glycosylated hemoglobin (HbA1c), fructosamine, and oral glucose tolerance test (OGTT)] and oxidative stress (urinary F2-isoprostanes) were measured along with lipid profile and high-sensitivity C-reactive protein (hsCRP) levels before and after supplementation. There were no significant baseline differences between groups. Compared to placebo, only the AC952 Aloe vera inner leaf gel powder resulted in significant reduction in total and low-density lipoprotein cholesterol (LDL-C) levels, glucose, and fructosamine. In the UP780 Aloe vera inner leaf gel powder standardized with 2% aloesin group, there were significant reductions in HbA1c, fructosamine, fasting glucose, insulin, and HOMA. Only the UP780 aloe group had a significant reduction in the F2-isoprostanes compared to placebo. Standardized aloe preparations offer an attractive adjunctive strategy to revert the impaired fasting glucose and impaired glucose tolerance observed in conditions of prediabetes/metabolic syndrome.

Aloe-induced Toxic Hepatitis

Aloe has been widely used in phytomedicine. Phytomedicine describes aloe as a herb which has anti-inflammatory, anti-proliferative, anti-aging effects. In recent years several cases of aloe-induced hepatotoxicity were reported. But its pharmacokinetics and toxicity are poorly described in the literature. Here we report three cases with aloe-induced toxic hepatitis. A 57-yr-old woman, a 62-yr-old woman and a 55-yr-old woman were admitted to the hospital for acute hepatitis. They had taken aloe preparation for months. Their clinical manifestation, laboratory findings and histologic findings met diagnostic criteria (RUCAM scale) of toxic hepatitis. Upon discontinuation of the oral aloe preparations, liver enzymes returned to normal level. Aloe should be considered as a causative agent in hepatotoxicity.

Aloe Supplements Enhance Bioavailability of Vitamin C and B12 in Older Adults

Vitamin/supplement intake is associated with decreased mortality. Aloe vera, a botanical is consumed by 50% of the US population and may affect bioavailability of vitamins. In a small study, Aloe improved vitamin C absorption. Since oral B12 is deficient in vegetarians and in aging, we tested the effect of 2 Aloe vera preparations compared to placebo on the bioavailability of vitamins, C and B12, in older healthy human volunteers. In a randomized cross-over trial, subjects (40–80 yrs, n=15) received either Aloe whole leaf extract (AL with vitamins B12, 1mg and vitamin C 500 mg) or aloe fillet gel (AG with vitamins) or water (with vitamins) and blood was obtained fasting and following 1,2,4,6,8 and 24 hours post-ingestion of aloe/water with 1 week between treatments. AG and AL did not affect lipids or glucose. AG significantly increased plasma Oxygen radical absorbance capacity (ORAC) at 4 and 24 hrs while AL significantly increased it at 4 hrs compared to baseline and placebo (AUC, 24h, p<0.05). AG significantly increased plasma vitamin C at 4,6,8 and 24 hrs and AL significantly increased it at 4 and 6 hrs (AUC, 8 and 24h, P<0.02). AG and AL significantly increased serum vitamin B12 levels at 1 and 2 hrs. Aloe preparations are well-tolerated and enhance bioavailability of vitamins C and B12 and ORAC. This could have major implications with regards to supplementation of vitamins to target chronic diseases, especially in elderly.

Effect of Aloe vera preparations on the human bioavailability of vitamins C and E

There are no literature references describing the effect of consumption of Aloe vera liquid preparations on the absorption of water- or fat-soluble vitamins. There is a very large population worldwide which consume vitamins and many people also consume Aloe. Thus we report the effect of Aloe on the human absorption of vitamins C and E, the most popular vitamin supplements. The plasma bioavailability of vitamins C and E were determined in normal fasting subjects, with eight subjects for vitamin C and ten subjects for vitamin E. In a random crossover design, the subjects consumed either 500 mg of ascorbic acid or 420 mg of vitamin E acetate alone (control), or combined with 2 oz of two different Aloe preparations (a whole leaf extract, or an inner fillet gel). Blood was collected periodically up to 24 h after consumption. Plasma was analyzed for ascorbate and tocopherol by-HPLC with UV detection. There was no significant difference in the areas under the plasma ascorbate-time curves among the groups sincerely due to large differences within the groups. For comparative purposes the control area was 100%. The Aloe Gel area was 304%, and Aloe Whole Leaf 80%. Only Aloe Gel caused a significant increase in plasma ascorbate after 8 and 24 h. For vitamin E, the results for the relative areas were control 100%, Gel 369%, and Leaf (198%). Only the Aloes produced a significant increase in plasma tocopherol after 6 and 8 h. Both Aloes were significantly different from the control after 8 h. Aloe Gel was significantly different from the baseline after 24 h. The Aloes slowed down the absorption of both vitamins with maximum concentrations 2-4 h later than the control. There was no difference between the two types of Aloe. The results indicate that the Aloes improve the absorption of both vitamins C and E. The absorption is slower and the vitamins last longer in the plasma with the Aloes. Aloe is the only known supplement to increase the absorption of both of these vitamins and should be considered as a complement to them.

Evidence for the efficacy and safety of topical herbal drugs in dermatology: Part I: Anti-inflammatory agents

Topical herbal drugs have for centuries been used for treating skin ailments. Although they are currently widely accepted by patients, their scientific esteem among dermatologists in particular is limited. A variety of herbal drugs for topical application deserves consideration regarding their widespread use or their still ill-defined potential with respect to their benefit/risk ratio. Clinically, camomile (Chamomilla recutita) and hamamelis preparations look particularly well documented. While the final proof of efficacy in common dermatoses such as atopic dermatitis is still lacking, there is fairly ample evidence for their activity against cutaneous inflammation in man, as may be deduced from experiments with normal volunteers. With Hamamelis virginiana this looks paricularly promising, as unwanted effects related to the drug are virtually absent. With camomile preparations the degree of safety seems to depend largely on the plant used. Some herbal drugs clearly need further analysis until their value can be determined. This includes the frequently-used aloe preparations. This is the more remarkable as huge numbers of in vitro studies are available. Arnica is fairly unique in so far as the lack of proof of efficacy strongly contrasts to its sensitization potential. So far, in particular dermatitis and related disorders can be considered potential indications for topical herbal antiinflammatory drugs. Studies in psoriasis vulgaris should also be performed addressing long-term application. In this context such fairly ill-defined drugs as Mahonia deserve attention.