Potential therapeutic applications of tea in dermatology

Efficacy of anti-sebum moisturizing cream containing 2% l-carnitine and 5% epigallocatechin gallate in seborrhea: A randomized clinical trial

BACKGROUND

Seborrhea leads to facial greasiness and unpleasant feeling. People with seborrhea also have trouble with selecting moisturizers. l-Carnitine and epigallocatechin gallate (EGCG) are reported anti-sebum properties. However, neither efficacy comparison nor the combination effect of the two topical anti-sebum agents was studied. Moisturizing cream with these agents is supposed to provide skin with an optimal water-oil balance.

AIMS

To compare the efficacy of moisturizer containing 2% l-carnitine or 5% EGCG alone on sebum controlling, and the synergistic effect of these two agents.

METHODS

Three study creams were formulated by adding three kinds of anti-sebum agents which were 2% l-carnitine, 5% EGCG, and 2% l-carnitine plus 5% EGCG in moisturizing cream base of dimethicone and glycerin. A randomized clinical trial was conducted. Ninety subjects, divided into three groups, applied the cream for 4 weeks. Sebum level, skin capacitance, and transepidermal water loss (TEWL) were evaluated at Weeks 0, 1, 2, and 4. Life qualities and subjective outcomes were assessed before and after treatment.

RESULTS

The mean sebum reduction from baseline was statistically significant in all treatment groups (p < 0.01). The median time to oil control was longer in l-carnitine group. The combine group had significantly greater anti-sebum efficacy than l-carnitine group (p = 0.009). All three groups had significant improvement of other objective parameters and subjective outcomes.

CONCLUSIONS

The anti-sebum moisturizing cream exhibited beneficial effect on the sebum reduction with improve skin hydration in people with seborrhea and made users satisfied. The EGCG group and the combine group show the greater anti-sebum effect than the l-carnitine group.

A Comprehensive Review of the Potential Use of Green Tea Polyphenols in the Management of COVID-19

Green tea is produced from Camellia sinensis (L.) buds and leaves that have not gone through the oxidation and withering processes used to produce black and oolong teas. It was originated in China, but its cultivation and production have expanded to other Eastern Asian countries. Several polyphenolic compounds, including flavandiols, flavonols, flavonoids, and phenolic acids, are found in green tea and may constitute greater than 30% of the dry weight. Flavonols, especially catechins, represent the majority of green tea polyphenols. Green tea polyphenolic compounds have been reported to confer several health benefits. This review describes the potential use of green tea polyphenols in the management of coronavirus disease 2019 (COVID-19). The immunomodulatory, antibacterial, antioxidant, and anti-inflammatory effects of green tea polyphenols have also been considered in this review. In addition to describing the bioactivities associated with green tea polyphenols, this review discusses the potential delivery of these biomolecules using a nanoparticle drug delivery system. Moreover, the bioavailability and toxicity of green tea polyphenols are also evaluated.

Effectiveness of topical green tea against multidrug-resistant Staphylococcus aureus in cases of primary pyoderma: An open controlled trial

Background

Antimicrobial activity of green tea against Staphylococcus aureus both in vitro and in vivo has been reported recently. Studies on clinical efficacy and safety of green tea as antibacterial agent against S. aureus in human cases are rare.

Objectives

To evaluate the clinical effectiveness and safety of topical green tea on primary pyoderma caused by S. aureus. We also attempted to determine the minimum inhibitory concentration of green tea against S. aureus and methicillin-resistant S. aureus.

Methods

Open label, prospective, placebo-controlled study included community-acquired primary pyoderma cases caused by S. aureus. Severity grading was done on a scale of 1-5. Green tea ointment 3% and placebo ointment were used. Cure was defined on the basis of negative culture and assessment of clinical improvement. Minimum inhibitory concentration was determined by agar dilution method. Data were analyzed using Statistical Package for Social Sciences (SPSS) software version 16.

Results

Of the 372 patients, 250 received green tea and 122 received placebo. Multidrug-resistant S. aureus was isolated in 89.1% in green tea group and 81.1% in placebo group, respectively. Methicillin-resistant S. aureus was isolated in 24 patients. Cure was seen in 86% in green tea group and 6.6% in placebo group which was statistically very significant. The number of days for comprehensive cure in green tea group was 9.2 ± 6.4 days. All patients with methicillin-resistant S. aureus infection in the green tea group were cured. Minimum inhibitory concentration of green tea against S. aureus was 0.0265 ± 0.008 μg/ml and against methicillin-resistant S. aureus was 0.0205 ± 0.003 μg/ml.

Limitations of the Study

Comparative trial was not conducted in the same patient with different lesions; children less than seven years were not considered as the school authorities did not permit for younger children to be included in the study and true randomization and blinding of investigators were not done.

Conclusions

Green tea has a significant antibacterial effect against multidrug-resistant S. aureus. Minimum inhibitory concentration of green tea is established and is promising in methicillin-resistant S. aureus infections.

The use of green tea extract in cosmetic formulations: not only an antioxidant active ingredient

Green tea (GT) extracts contain polyphenols, known to be effective free radical scavengers, and other ingredients that could also provide benefits to the skin. This is a report on clinical studies using objective, noninvasive methods to evaluate the effects of cosmetic formulations containing GT. Experimental formulations were supplemented or not (vehicle) with 6% Camellia sinensis glycolic leaf extracts (GT). These formulations were applied to the forearm skin of 24 volunteers, and their effects were evaluated before and after 2 hours, 15 and 30 days according to the following parameters: stratum corneum water content, transepidermal water loss, skin viscoelastic-to-elastic ratio (Uv/Ue), and microrelief. The volunteers were instructed not to apply any formulation in an area of the forearm (control area). Experimental formulations (GT) increased skin moisture in the long-term study, indicating that GT has a prolonged moisturizing effect. The Uv/Ue was significantly enhanced after 30 days of topical application of the experimental formulation when compared with vehicle and control. After 15-30 days, skin microrelief was significantly improved due to a reduction in skin roughness. The results suggest that GT-containing cosmetic formulations have pronounced moisturizing effects and improve skin microrelief.

Phytoceuticals: the new 'physic garden' for asthma and chronic obstructive pulmonary disease

Phytoceuticals (non-nutritional but beneficial plant chemicals) merit investigation as pharmacotherapy for asthma and chronic obstructive pulmonary disease (COPD). Although asthma is mostly treated adequately, COPD is not. Thus, there is a need for new drugs with improved therapeutic benefit, especially in COPD. Recent interest in herbal remedies has redirected attention towards plants as sources of improved treatments for lung disease. Phytoceuticals from a variety of plants and plant products, including butterbur, English ivy, apples, chocolate, green tea and red wine, demonstrate broad-spectrum pharmacotherapeutic activities that could be exploited in the clinic. Well-designed clinical trials are required to determine whether these beneficial activities are reproduced in patients, with the prospect that phytoceuticals are the new physic garden for asthma and COPD.

Interventions for preventing non-melanoma skin cancers in high-risk groups

BACKGROUND

Some groups of people have a greater risk of developing common non-melanoma skin cancers (NMSC).

OBJECTIVES

To evaluate interventions for preventing NMSC in people at high risk of developing NMSC.

SEARCH STRATEGY

We searched the Cochrane Skin Group Specialised Register (March 2007), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2007, MEDLINE (from 2003 to March 2007), EMBASE (from 2005 to March 2007), the metaRegister of Controlled Trials (February 2007). References from trials and reviews were also searched. Pharmaceutical companies were contacted for unpublished trials.

SELECTION CRITERIA

Randomised controlled trials of adults and children at high risk of developing NMSC.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and assessed their methodological quality.

MAIN RESULTS

We identified 10 trials (7,229 participants) that assessed a variety of interventions. One trial found T4N5 liposome lotion significantly reduced the rate of appearance of new BCCs in people with xeroderma pigmentosum. One of three trials of renal transplant recipients showed a significantly reduced risk of new NMSCs when acitretin was compared to placebo (relative risk (RR) 0.22 95% confidence interval (CI) 0.06 to 0.90) and no significant difference in risk of adverse events in two trials (RR 1.80, 95% CI 0.70 to 4.61). In three trials conducted in people with a history of NMSC, the evidence was inconclusive for the development of BCCs for retinol or isoretinoin. However the risk of a new SCC in one trial (HR 1.79, 95% CI 1.16 to 2.76) and adverse events in another trial (RR 1.76 95% CI 1.57 to 1.97) were significantly increased in the isotretinoin group compared with placebo. In one trial selenium showed a reduced risk of other types of cancer compared with placebo (RR 0.65, 95% CI 0.50 to 0.85) but also a significantly elevated risk of a new NMSC (HR 1.17 95% CI 1.02 to 1.34). The evidence for one trial of beta-carotene was inconclusive; and there was a trend towards fewer new NMSC in a trial of a reduced fat diet (RR 0.16, 95% CI 0.02 to 1.31), p=0.09.

AUTHORS' CONCLUSIONS

Some preventative treatments may benefit people at high risk of developing NMSC, but the ability to draw firm conclusions is limited by small numbers of trials, often with one trial per intervention or with inconsistent results between studies.

Tea polyphenols for health promotion

People have been consuming brewed tea from the leaves of the Camellia sinensis plant for almost 50 centuries. Although health benefits have been attributed to tea, especially green tea consumption since the beginning of its history, scientific investigations of this beverage and its constituents have been underway for less than three decades. Currently, tea, in the form of green or black tea, next to water, is the most widely consumed beverage in the world. In vitro and animal studies provide strong evidence that polyphenols derived from tea may possess the bioactivity to affect the pathogenesis of several chronic diseases. Among all tea polyphenols, epigallocatechin-3-gallate has been shown to be responsible for much of the health promoting ability of green tea. Tea and tea preparations have been shown to inhibit tumorigenesis in a variety of animal models of carcinogenesis. However, with increasing interest in the health promoting properties of tea and a significant rise in scientific investigation, this review covers recent findings on the medicinal properties and health benefits of tea with special reference to cancer and cardiovascular diseases.

Cutaneous photodamage, oxidative stress, and topical antioxidant protection

New methods to protect skin from photodamage from sun exposure are necessary if we are to conquer skin cancer and photoaging. Sunscreens are useful, but their protection is not ideal because of inadequate use, incomplete spectral protection, and toxicity. Skin naturally uses antioxidants (AOs) to protect itself from photodamage. This scientific review summarizes what is known about how photodamage occurs; why sunscreens--the current gold standard of photoprotection--are inadequate; and how topical AOs help protect against skin cancer and photoaging changes. This review is intended to be a reference source, including pertinent comprehensive reviews whenever available. Although not all AOs are included, an attempt has been made to select those AOs for which sufficient information is available to document their potential topical uses and benefits. Reviewed are the following physiologic and plant AOs: vitamin C, vitamin E, selenium, zinc, silymarin, soy isoflavones, and tea polyphenols. Their topical use may favorably supplement sunscreen protection and provide additional anticarcinogenic protection. (J Am Acad Dermatol 2003;48:1-19.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should have an understanding of current information about how the sun damages skin to produce skin cancer and photoaging changes, how the skin naturally protects itself from the sun, the shortcomings of sunscreens, and the added advantages of topical AOs for photoprotection.

Dietary factors in the prevention and treatment of nonmelanoma skin cancer and melanoma

BACKGROUND

The endogenous antioxidant system of the skin scavenges reactive oxygen species and combats ultraviolet induced oxidative skin damage. Supporting this cutaneous defense system with topical or oral antioxidants may provide a successful strategy for the treatment and prevention of skin cancer.

OBJECTIVE

Review evidence regarding treatment and prevention of melanoma and nonmelanoma skin cancers through dietary and topical antioxidants, vitamins, and herbal supplements.

METHODS

Literature review.

RESULTS

Review of the literature demonstrates that the administration of synthetic retinoids has not proved beneficial for otherwise healthy patients with nonmelanoma skin cancer. Selenium supplementation has reduced the incidence of several internal malignancies but not of nonmelanoma skin cancer. Synergistic use of beta-carotene with vitamins C and E has demonstrated prophylaxis against reactive oxygen radicals involved in nonmelanoma skin cancer and reduced sunburn reactions significantly. 1,25-dihydroxyvitamin D3 analog CB1093 has demonstrated promise as a therapeutic agent in the regression of the early stages of melanoma in specific cell lines.

CONCLUSION

Delivery of exogenous antioxidants in combination appears to be a more successful strategy for enhancing the cutaneous antioxidant system than the administration of isolated antioxidants alone. Vitamin D analogs may have a role in the medical therapy of melanoma. However, avoiding exposure to ultraviolet light appears to be the only true panacea against the development of melanoma and NMSC.

A review of latest research findings on the health promotion properties of tea

Important progress has been made in the past five years concerning the effects of green and black tea on health. Experimentation with new accurate tools provide useful information about the metabolism of tea components in the body, their mode of action as antioxidants at the cellular level and their protective role in the development of cancer, cardiovascular disease and other pathologies. The use of tea components as nutraceuticals and functional foods are also discussed.