Antibacterial Activity of Curcumin Against Periodontal Pathogens: A Systematic Review

Pre-clinical and clinical efficacy of curcumin as an anti-inflammatory agent for periodontitis. A systematic review

Introduction

There is ongoing exploration into herbal treatments to identify adjunct therapies with minimal side effects. One such treatment involves curcumin from turmeric (Curcuma longa). This study aims to review the efficacy of curcumin as an anti-inflammatory agent for periodontitis along with the mechanisms of action involved.

Methods

A systematic review of pre-clinical and clinical studies published on Scopus, PubMed, ScienceDirect, and Google Scholar up to May 2024 was employed following the PRISMA guidelines. Three tools were used for risk of bias assessment, namely the QUIN tool for in vitro studies, the SYRCLE's RoB for in vivo studies, and the Cochrane RoB 2 for RCTs. Finally, nineteen studies were included for review.

Results

This study highlights curcumin's efficacy in addressing periodontitis through diverse mechanisms. Curcumin demonstrated efficacy in attenuating inflammation within periodontal tissue by inhibiting several pro-inflammatory cytokines and mediators such as interleukin (IL)-1, IL-6, tumor necrosis factor (TNF)-α, matrix metalloproteinases (MMPs), prostaglandin E2 (PGE2), cyclooxygenase (COX)-2, while concurrently increasing IL-4 and IL-10. In addition, several transcription factors such as nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 1 (STAT1) were also inhibited by curcumin. Administration of curcumin has additionally been demonstrated to reduce other biomarkers of periodontitis, including C-reactive protein (CRP), alkaline phosphatase (ALP), and procalcitonin (PCT).

Conclusion

Curcumin has been shown to be effective as an adjunct therapeutic agent for periodontitis due to its anti-inflammatory effects by reducing the inflammatory response through a diverse range of mechanisms of action.

In vitro evaluation of anti-microbial efficacy of Trigonella foenum-graecum and its constituents on oral biofilms

Background and Objective

The extracts obtained from the leaves and seeds of Trigonella foenum-graecum (Fenugreek) are effective against various microbial infections. The phytoconstituents of Trigonella foenum-graecum have shown promising effects as anti-diabetics, anti-helmentic, anti-microbial, antifungal, and antipyretic, but its impact on oral pathogens is yet to be established. Therefore, the present study aimed to explore the antimicrobial efficacy of phytoconstituents of Trigonella foenum-graecum as compared to 0.2% chlorhexidine (CHX).

Materials and Methods

The methanolic extracts of Trigonella foenum-graecum i.e., fenugreek absolute (FA), diosgenin (DIO), and furanone (FU) were used in this study. The antimicrobial efficacy of these extracts was evaluated by testing the minimal inhibitory concentration, minimal bactericidal concentration (MBC), agar well-diffusion assay, colony-forming unit (CFU) count, and also by using confocal laser scanning microscopy (CLSM) against Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 35218, and Pseudomonas aeruginosa ATCC 27853.

Results

The results of the study demonstrated that Trigonella foenum-graecum has anti-microbial activity comparable to 0.2% CHX. Well-diffusion assay and CFU count assay of the extracts showed statistically significant (P < 0.001) results. MIC and MBC values were observed for FA, DIO, and FU compared to CHX against these selected test organisms. These results were confirmed by visual validation with CLSM.

Conclusion

The use of herbal alternatives in periodontics might prove to be advantageous. Trigonella foenum-graecum can be used as a promising alternative to CHX against S. aureus, E. faecalis, E. coli, and P. aeruginosa for the management of oral and periodontal infections.

Susceptibility of periodontal pathogens to a novel target-specific drug delivery system containing self-nanoemulsifying curcumin: An in vitro study

Background

Long-term use of many classic chemotherapeutic agents as adjuncts in the management of periodontitis has adverse complications, leading to seeking out naturopathic remedies. Although curcumin has been investigated in managing periodontitis, its therapeutic benefits have not been fully explored due to its limited solubility in an aqueous medium. This study aimed to develop a novel target-specific drug delivery system containing 1% self-nanoemulsifying curcumin (SNEC) in a hydroxypropylmethylcellulose (HPMC) matrix and evaluate the susceptibility of periodontal pathogens to this system in vitro.

Methods

Its antibacterial activity against Tannerella forsythia, Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans was evaluated and compared to pure nano-curcumin and SNEC alone by estimating their minimum inhibitory concentrations (MIC).

Results

The antibacterial activity of pure nano-curcumin, SNEC, and SNEC in HPMC against the four periodontal pathogens evaluated in terms of MIC was recorded in the range of 0.2‒0.4, 0.4‒0.8, and 0.2‒0.8 µg/mL, respectively. However, the MIC of all three curcumin formulations against the periodontal pathogens tested was higher than that of the standard moxifloxacin. While both pure nano-curcumin and SNEC showed increasing values of inhibition zones with increasing concentrations on disk diffusion assay, lower concentrations of SNEC in HPMC did not show a zone of inhibition against the tested pathogens.

Conclusion

The novel delivery system containing SNEC in HPMC may be a potential adjunct in managing periodontitis due to its probable sustained antimicrobial activity against the tested periodontal pathogens.

The impact of curcumin on migraine: A comprehensive review

Migraine, a neurovascular condition, is a chronic and lifelong disease that affects about 15% of the population worldwide. Although the exact pathophysiology and etiology of migraine are still unclear, oxidative stress, inflammation, and neuroendocrine imbalances are identified as the critical risk factors for migraine attacks. Curcumin is an active component and a polyphenolic diketone compound extracted from turmeric. Curcumin is a promising candidate for preventing and controlling migraine due to its anti‑inflammatory, antioxidative, anti-protein aggregate, and analgesic effects. In the present review, we have evaluated experimental and clinical studies investigating the impact of liposomal curcumin and nano-curcumin on the frequency and severity of migraine attacks in patients. Although the results are promising, more studies should be conducted in this area to show the exact efficacies of curcumin on clinical symptoms of migraine and investigate its potential mechanisms.

Curcumin-piperine co-supplementation and human health: A comprehensive review of preclinical and clinical studies

Curcumin is extracted from the rhizomes Curcuma longa L. It is known for its anti-inflammatory and anti-oxidant activities. Despite its safety and potential for use against various diseases, curcumin's utility is restricted due to its low oral bioavailability. Co-administration of curcumin along with piperine could potentially improve the bioavailability of curcumin. The present review aimed to provide an overview of the efficacy and safety of curcumin-piperine co-supplementation in human health. The findings of this comprehensive review show the beneficial effects of curcumin-piperine in improving glycemic indices, lipid profile and antioxidant status in diabetes, improving the inflammatory status caused by obesity and metabolic syndrome, reducing oxidative stress and depression in chronic stress and neurological disorders, also improving chronic respiratory diseases, asthma and COVID-19. Further high-quality clinical trial studies are needed to firmly establish the clinical efficacy of the curcumin-piperine supplement.

Synthesis, Characterization and Biological Evaluation of Novel Benzamidine Derivatives: Newer Antibiotics for Periodontitis Treatment

Periodontal disease (PD) is complex polymicrobial disease which destroys tooth-supporting tissue. Although various synthetic inhibitors of periodontitis-triggering pathogens have been recognized, their undesirable side effects limit their application. Hence, the present study intended to perform the synthesis, characterization, antimicrobial evaluation, and cytotoxicity analysis of novel benzamidine analogues (NBA). This study involved the synthesis of novel imino bases of benzamidine (4a–c), by reacting different aromatic aldehydes with 2-(4-carbamimidoylphenoxy) acetohydrazide (3), which was synthesized by the hydrazination of ethyl 2-(4-carbamimidoylphenoxy) acetate (2), the derivative of 4-hydroxybenzene carboximidamide (1). This was followed by characterization using FTIR, ¹H, ¹³C NMR and mass spectrometry. All synthesized compounds were further tested for antimicrobial potential against PD-triggering pathogens by the micro broth dilution method. The cytotoxicity analysis of the NBA against HEK 293 cells was conducted using an MTT assay. The present study resulted in a successful synthesis of NBA and elucidated their structures. The synthesized NBA exhibited significant antimicrobial activity values between 31.25 and 125 µg/mL against tested pathogens. All NBA exhibited weak cytotoxicity against HEK 293 cells at 7.81 µg, equally to chlorhexidine at 0.2%. The significant antimicrobial activity of NBA against PD-triggering pathogens supports their potential application in periodontitis treatment.