Toxicological and anti-tumor effects of a linden extract (Tilia platyphyllos Scop.) in a HPV16-transgenic mouse model

Bio-guided isolation of anti-inflammatory compounds from Tilia tuan Szyszyl. flowers via in vitro and in silico study

ETHNOPHARMACOLOGICAL RELEVANCE

Tilia tuan Szyszyl. is a perennial arboreal plant renowned for its medicinal and economic significance. All the roots, stems, leaves, flowers, and fruits have been used medicinally by the folk Bai and Yi people in Yunnan province, China, to treat inflammation, rheumatism and pain for a long time. The detailed chemical constituents and their anti-inflammatory mechanisms remain unexplored.

AIM OF THE STUDY

The objective of this study was to investigate the main anti-inflammatory constituents of T. tuan flowers through bio-guided isolation and to evaluate their anti-inflammatory effects relevant to its traditional medicinal use.

MATERIAL AND METHODS

Bio-guided isolation was conducted on the extract of T. tuan flowers using a combination of column chromatography and preparative HPLC. The structures were established by a combination of extensive spectroscopic analyses and single-crystal X-ray diffraction analysis. The anti-inflammatory activity in vitro was evaluated by measuring the inhibition of nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. TNF-α and IL-6 levels were evaluated by ELISA. The expression of COX-2 and NF-κB was assayed via western blotting, and in-silico molecular docking was conducted to explore the potential mechanism.

RESULTS

Twenty-two compounds, including ten flavonoids (1-10), seven phenylpropanoids (11-17), three triterpenoids (19-21), one sterol glucoside 18, and one glyceride 22, were identified from T. tuan flowers for the first time. Among them, 1 is a new compound. It is noted that 1, 5, 7, 8, 10, 17, and 22 exhibited remarkable anti-inflammatory activity against NO production with a range of 5.2-34.5 μM, superior to the positive control L-NMMA. Moreover, the new compound 1 inhibited significantly inflammatory factors IL-6 and TNF-α.

CONCLUSION

The results show that flavonoids including the new one and the phenyl-propanoid are the primary active constituents of T. tuan flowers, responsible for its ethno-pharmacological uses on osteoarthritis and rheumatism. T. tuan flowers could be a promising therapeutic agent to modulate inflammatory diseases.

Investigating the Effect of the Crosslinking Factor on the Properties of Hydrogel Materials Containing Tilia platyphyllos Hydrolate

The use of natural ingredients in recent years has been of great importance in many industries and medicine. In biomedical applications, hydrogel materials also play a significant role. In view of this, the aim of this study was to synthesize and characterize hydrogel materials enriched with broadleaf linden hydrolate. An important aspect was to carry out a series of syntheses with varying types and amounts of crosslinking agents so as to test the possibility of synthesizing materials with controlled properties. The obtained hydrogels were subjected to detailed physicochemical analysis. The results of the tests confirmed the relationship between the selected properties and the type of crosslinking agent used. A crosslinking agent with a lower molar mass (575 g/mol) results in a material with a compact and strongly crosslinked structure, which is characterized by high surface roughness. The use of a crosslinking agent with a molecular weight of 700 g/mol resulted in a material with a looser-packed polymer network capable of absorbing larger amounts of liquids. The work also proved that regardless of the type of crosslinking agent used, the addition of linden hydrolate provides antioxidant properties, which is particularly important in view of the target biomedical application of such materials.

Study on the antineoplastic and toxicological effects of pomegranate (Punica granatum L.) leaf infusion using the K14-HPV16 transgenic mouse model

Punica granatum L. (pomegranate) has been used in functional foods due to its various health benefits. However, the in vivo biological potential of its leaf remains little known. This study has aimed to characterize the antineoplastic and toxicological properties of using pomegranate leaf infusion (PLI) on transgenic mice carrying human papillomavirus (HPV) type 16 oncogenes. Thirty-eight mice were divided into 3 wild-type (WT) and 3 transgenic (HPV) groups, with exposure to 0.5% PLI, 1.0% PLI, and water. The animals' body weight, drink and food consumption were recorded. Internal organs, skin samples and intracardiac blood were collected to evaluate toxicological parameters, neoplastic lesions and oxidative stress. The results indicated that PLI was safe as no mortality, no behavioural disorders and no significant differences in the levels of microhematocrit, serum biochemical markers, internal organ histology, and oxidative stress was found among the WT groups. Histological analysis revealed that HPV animals that consumed PLI exhibited reduced hepatic, renal and cutaneous lesions compared with the HPV control group. Low-dose PLI consumption significantly diminished renal hydronephrosis lesions and relieved dysplasia and carcinoma lesions in the chest skin. Oxidative stress analysis showed that low-dose PLI consumption may have more benefits than high-dose PLI. These results suggest that oral administration of PLI has the potential to alleviate non-neoplastic and neoplastic lesions against HPV16-induced organ and skin injuries, though this requires further scientific research studies.

The Red Seaweed Grateloupia turuturu Prevents Epidermal Dysplasia in HPV16-Transgenic Mice

The role of dietary profiles in promoting or reducing the risk of multiple types of cancer is increasingly clear, driving the search for balanced foods and nutraceuticals. The red seaweed Grateloupia turuturu has been used as human food showing a balanced nutritional profile. This study aims to test in vivo chemopreventive effects of G. turuturu against cutaneous pre-malignant lesions in transgenic mice for the human papillomavirus type 16 (HPV16). Forty-four female HPV^+/− or HPV^−/− mice received a standard diet or were supplemented with 10% G. turuturu for 22 consecutive days. Cutaneous lesions (ear and chest skin) were identified histologically. Complementarily, the weights and histology of internal organs as well as blood biochemical and DNA integrity parameters were also assessed. G. turuturu consistently reduced the incidence of epidermal dysplasia induced by HPV16 on both cutaneous sites. Moreover, biochemical, DNA integrity and histological analyses confirmed G. turuturu edibility as no signs of toxicity were found. Dietary supplementation with G. turuturu is an effective and safe chemopreventive strategy in this model.