Angiomodulatory properties of Rhodiola spp. and other natural antioxidants

3,5-Dimethyl-8-methoxy-3,4-dihydro-1H-isochromen-6-ol Attenuates Ulcerative Colitis via Targeting NLRP3 in Mice

3,5-Dimethyl-8-methoxy-3,4-dihydro-1H-isochromen-6-ol (DMD) is a polyketide compound obtained from the endophytic fungus Penicillium sp. HJT-A-10 of Rhodiola tibetica. R. tibetica is a nourishing food and also used in traditional Chinese medicine and Xizang medicine. In dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice, DMD significantly alleviated the pathological symptom of UC. Network pharmacology studies have shown that nucleotide-binding domain-like receptor family pyrin domain containing (NLRP) 3 is the primary target protein of DMD associated with anti-UC. In molecular biology studies, DMD suppressed the activation of NLRP3 and decreased the expression of downstream inflammatory proteins and pro-inflammatory cytokines in UC. The finding was further verified in knockout mice. DMD lost the effect of attenuating DSS-induced UC in NLRP3-/- mice. In conclusion, this study demonstrates that DMD reduces inflammatory response and balances the barrier integrity to attenuate UC via targeting NLRP3, and DMD is a potential natural agent or dietary supplement for attenuating UC.

Phytochemical Profiles, Antioxidant Activity and Antiproliferative Mechanism of Rhodiola rosea L. Phenolic Extract

The phenolic profiles, antioxidant activity, antiproliferative property and the underlying molecular mechanisms of cell apoptosis of Rhodiola rosea free phenolic (RFE) were analyzed in this work. Overall, Rhodiola rosea rhizome phenolic extract (RE) contained Rhodiola rosea rhizome free phenolic extract (RFE) and Rhodiola rosea rhizome bound phenolic extract (RBE). Compared with RBE, RFE contained higher phenolic contents and possessed stronger antioxidant activity. High-performance liquid chromatography (HPLC) results demonstrated that the main phenolics of were epigallocatechin (EGC), epigallocatechin gallate (EGCG), gallic acid (GA) and catechin. Gas chromatography–mass spectrometry (GC-MS) analysis found that Rhodiola rosea L. was rich in volatile phytochemicals. In addition, many types of vitamin E and a few kinds of carotenoids were found in Rhodiola rosea. In addition, the main compounds in RFE (GA, EGC, EGCG) and RFE all exhibited excellent antiproliferative activity, indicating the antiproliferative activity of RFE was partly attributed to the synergy effects of the main compounds. Further study confirmed that RFE could block 16.99% of HepG2 cells at S phase and induce 20.32% programmed cell death compared with the control group. Specifically, RFE dose-dependently induced cell apoptosis and cell cycle arrest via modulating the p53 signaling pathway including up-regulation of the expression of p53 and Bax while down-regulation of the Bcl-2, cyclin D1 and CDK4 levels. Therefore, RFE exhibited the potential of being developed as an auxiliary antioxidant and a therapeutic agent for cancer.

Curcumin and Wnt/β‑catenin signaling in exudative age‑related macular degeneration (Review)

Curcumin is a natural product widely used due to its pharmacological effects. Nevertheless, only a limited number of studies concerning the effects of curcumin on exudative age‑related macular degeneration (AMD) is currently available. Since ophthalmic diseases, including exudative AMD, have a marked impact on public health, the prevention and therapy of ophthalmic disorders remain of increasing concern. Exudative AMD is characterized by choroidal neovascularization (CNV) invading the subretinal space, ultimately enhancing exudation and hemorrhaging. The exudative AMD subtype corresponds to 10 to 15% of cases of macular degeneration; however, the occurrence of this subtype has been reported as the major cause of vision loss and blindness, with the occurrence of CNV being responsible for 80% of the cases with vision loss. In CNV increased expression of VEGF has been observed, stimulated by the overactivation of Wnt/β‑catenin signaling pathway. The stimulation of the Wnt/β‑catenin signaling pathway is responsible for the activation of several cellular mechanisms, simultaneously enhancing inflammation, oxidative stress and angiogenesis in numerous diseases, including ophthalmic disorders. Some studies have previously demonstrated the possible advantage of the use of curcumin for the inhibition of Wnt/β‑catenin signaling. In the present review article, the different mechanisms of curcumin are described concerning its effects on oxidative stress, inflammation and angiogenesis in exudative AMD, by interacting with Wnt/β‑catenin signaling.

The GLP-1R Agonist Exendin-4 Attenuates Hyperglycemia-Induced Chemoresistance in Human Endometrial Cancer Cells Through ROS-Mediated Mitochondrial Pathway

This study aimed to assess the effects of the antidiabetic drug Exendin-4 (Exe-4), a GLP-1 receptor agonist, on the response of human endometrial cancer cells to chemotherapy under high glucose (HG) conditions. Cell viability was detected using a cell counting kit (CCK)-8. Cell apoptosis and reactive oxygen species (ROS) levels were measured by flow cytometry. Gene expression was evaluated by real-time PCR and immunoblotting. The chemotherapeutic drug cisplatin (DDP) dose-dependently inhibited both human endometrial adenocarcinoma Ishikawa and HEC1B cells, a response reversed by HG. Meanwhile, Exe-4 attenuated hyperglycemia’s effect by elevating intracellular lactate dehydrogenase (LDH) and ROS production. Similarly, DDP-induced elevation of intracellular rhodamine123 was attenuated by HG, and Exe-4 reversed HG’s impact. The chemoresistance genes multidrug resistance-associated protein 1 (MRP1) and P-glycoprotein (Pgp) were upregulated. At the same time, topoisomerase II (TOPO II) was downregulated under HG conditions, suggesting HG-induced chemoresistance. Exe-4 did not significantly influence the above genes. DDP downregulated Bcl-2 and Bcl-XL and upregulated Bax, cytosolic cytochrome c, and PARP under normal glucose (NG) versus HG conditions, and Exe-4 attenuated these effects. Upstream of Bax/Bcl, acetylated P53 was upregulated by DDP and downregulated by HG, whose effect was reversed by Exe-4. DPP treatment significantly induced apoptosis and cell cycle arrest in the S phase under NG, and HG reduced these effects. Prolonged exposure to HG induces DDP chemoresistance in human endometrial cancer cells but is alleviated by Exe-4.

Resveratrol as Inducer of Autophagy, Pro-Survival, and Anti-Inflammatory Stimuli in Cultured Human RPE Cells

Purpose: To investigate the mechanism by which resveratrol acts upon retinal pigment epithelial (RPE) cells and to characterize its effect upon autophagy, survival, and inflammation, with consequent implications to treatment for age-related macular degeneration (AMD). Methods: Cultured ARPE-19 cells were exposed to 10 and 50 μM resveratrol. Cell survival/death was determined by annexin-FITC/propidium iodide using flow cytometry, while autophagy was studied by detecting autophagic vacuoles formation (acridine orange and transmission electron microscopy), as well as LC3II/I ratio and p62 expression by Western blot. In addition, time-lapse confocal microscopy of a pDENDRA-LC3 expression vector was performed to detect autophagy in transfected ARPE-19 cells under the different treatment conditions. Inhibition of proteasomal and autophagy-lysosomal fusion was carried out by MG-132 and chloroquine, respectively, while induction of autophagy was achieved by rapamycin treatment. Detection of secreted cytokines by ARPE-19 cells using Human XL Cytokine Array was performed under oxidative stress (H₂O₂) and resveratrol treatments, respectively. Results: Resveratrol induced autophagy in ARPE-19 cells as determined by augmented presence of autophagic vacuoles, increased LC3II/I ratio and decreased p62 expression, as well as time-lapse confocal microscopy using pDENDRA-LC3 expression vector. Resveratrol acted similarly to proteasomal inhibition and downstream of mammalian target of rapamycin (mTOR), since upstream inhibition of autophagy by 3-methyladenine could not inhibit autophagy in ARPE-19 cells. Co-treatmeant by rapamycin and/or proteasome inhibition showed no additive effect upon autophagy induction. ARPE-19 cells treated by resveratrol showed lower cell death rate compared to untreated controls. Resveratrol induced a specific anti-inflammatory response in ARPE-19 cells. Conclusions: Resveratrol can induce autophagy, pro-survival, and anti-inflammatory stimuli in ARPE-19 cells, properties which could be plausible to formulate future treatment modalities for AMD.

Therapeutic potential of curcumin in eye diseases

Curcumin (diferuloylmethane) derived from the rhizome of Curcuma longa L. has been used for thousands of years in traditional Chinese medicine and Ayurvedic medicine in Asian countries to treat liver diseases, rheumatoid diseases, diabetes, atherosclerosis, infectious diseases and cancer. It exhibits a wide range of pharmacological properties, which include antioxidant, anti-inflammatory, antimutagenic, antimicrobial and anticancer activity. Herein the mechanisms of curcumin impact on oxidative stress, angiogenesis and inflammatory processes are described indicating that curcumin use may inhibit those pathological conditions and restore body homeostasis. Its effectiveness was also proved for major eye diseases. In this review, the influence of curcumin on eye diseases, such as glaucoma, cataract, age-related macular degeneration, diabetic retinopathy, corneal neovascularization, corneal wound healing, dry eye disease, conjunctivitis, pterygium, anterior uveitis are reported. The analysis of a number of clinical and preclinical investigations indicates that curcumin may be used as a therapeutic agent in the treatment of various eye disorders.

Antioxidant and Antibacterial Activity of Roseroot (Rhodiola rosea L.) Dry Extracts

Roseroot (Rhodiola rosea L.) belongs to plants revealing adaptogenic properties, which are attributed to the presence of specific phenolic compounds and are reflected mainly as antioxidant activity. The aim of the present study was to determine the antioxidant and antibacterial activity of various products obtained from R. rosea (underground organs as well as their aqueous and ethanolic dry extracts) in relation to the chemical profiles of phenolic and essential oil compounds. The chemical profiles were determined by High-performance Liquid Chromatography with a diode-array detector (HPLC-DAD) and Gas chromatography-mass spectrometry (GC-MS), antioxidant activity by (1,1-Diphenyl-2-picrylhydrazyl) Scavenging Capacity Assay (DPPH), (2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) Scavenging Capacity Assay (ABTS) and Ferric Reducing Antioxidant Power Assay (FRAP) and antimicrobial properties were expressed as minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) values following the broth microdilutions method. The results show that the investigated samples differed in terms of their chemical compositions and biological activities. The extracts were more abundant in phenolic compounds (salidroside, tyrosol, and rosavin derivatives) in comparison to dried underground organs. The content of the determined phenolics in the analyzed extracts was affected by the solvent used for extraction. The ethanolic extract was characterized by the highest content of these substances in comparison to the aqueous one and the dried raw material, especially with regard to rosavin (969.71 mg/100 g). In parallel, this extract showed the strongest antioxidant and antibacterial activity. However, dried R. rosea underground organs also revealed strong antibacterial effects against, for example, Staphylococcus strains.

Angiogenesis modulation by exogenous antioxidants

Co-operation of the endogenous and exogenous defense system maintains redox homeostasis and is essential for health. The endogenous defense system includes enzymatic (e.g. superoxide dismutase, catalase) and non-enzymatic, low molecular-weight scavengers (e.g. glutathione, ascorbic acid). Pathogenesis of many serious diseases (e.g. cancer, ischemic heart disease) includes oxidative stress which can disturb angiogenesis, the process of formation of new blood vessels sprouting from the existing one. Antioxidants, through reduction of oxidative stress and influence on neovascularization, may modulate progress and results of therapy in those diseases where such processes play an important role. Herein the impact of exogenous antioxidants on angiogenesis and factors modulating this process is presented. Most synthetic antioxidants whose activity has been described (namely N-acetylcysteine, pentoxifylline, synthetic analogue of curcumin, synthetic analogue of epigallocatechin-3 gallate [EGCG], tripertenoids) exert an inhibitory effect on neovascularization. A similar effect was also exhibited by several natural origin antioxidants (e.g. resveratrol, EGCG), which suggests that their application in therapy might normalize excessive angiogenesis. Some natural origin antioxidants e.g. purple coneflower and preparations consisting of natural antioxidants such as Padma 28 and Immunal forte increase a too low baseline level of angiogenesis and decreases a too high level. These preparations exert a regulatory effect on and may normalize neovascularization. They can be used in the case of diseases associated with too low or too high angiogenesis.

Effect of hydro-alcoholic extract of Rhodiola imbricata on growth performance, immunomodulation, antioxidant level and blood biochemical parameters in broiler chickens at high altitude cold desert

Extremes of climate and hypobaric hypoxia cause poor growth performance in broiler chickens at high altitude.The current study was designed to investigate the effect of hydro-alcoholic extract of Rhodiola imbricata onantioxidant, cytokines, blood biochemical and growth performance of broilers at high altitude (3500 m). For invivostudy, one day-old broiler chicks of average initial body weight 36.40±0.42 g were randomly assigned to seven groups in three replicates (10 chicks in each replicate) as per completely randomized design. Experimental groups included control (fed basal diet), and treatment T1, T2, T3, T4, T5, and T6 which received hydro-alcoholic extract of Rhodiola imbricata in drinking water @ 100, 150, 200, 300, 400, and 800 mg/kg body weight of chicken respectively, along with basal diet. Blood samples were collected at 0, 21st, and 42nd day. HPLC analysis of extract revealed the presence of salidroside and p-tyrosol. As a result of this study, birds in T5 group had significantly higher body weight as compared to other groups. Furthermore, they had significantly higher total antioxidant capacity, free radical scavenging activity, interleukin-2, total protein, globulin, HDL level and lower malondialdehyde, interleukin-6, cholesterol, triglyceride, LDL, glucose, A/G, ALT, AST level as compared to control group. Our results suggest that, Rhodiola imbricata extract @ 400 mg/kg body weight of chicken, exhibited beneficial effect on growth performance and therefore, can be used as a phytogenic feed additive for broiler chickens.

Rhodiola rosea L.: an herb with anti-stress, anti-aging, and immunostimulating properties for cancer chemoprevention

Purpose of review

Rhodiola rosea extracts have been used as a dietary supplement in healthy populations, including athletes, to non-specifically enhance the natural resistance of the body to both physical and behavior stresses for fighting fatigue and depression. We summarize the information with respect to the new pharmacological activities of Rhodiola rosea extracts and its underlying molecular mechanisms in this review article.

Recent findings

In addition to its multiplex stress-protective activity, Rhodiola rosea extracts have recently demonstrated its anti-aging, anti-inflammation, immunostimulating, DNA repair and anti-cancer effects in different model systems. Molecular mechanisms of Rhodiola rosea extracts's action have been studied mainly along with one of its bioactive compounds, salidroside. Both Rhodiola rosea extracts and salidroside have contrast molecular mechanisms on cancer and normal physiological functions. For cancer, Rhodiola rosea extracts and salidroside inhibit the mTOR pathway and reduce angiogenesis through down-regulation of the expression of HIF-1α/HIF-2α. For normal physiological functions, Rhodiola rosea extracts and salidroside activate the mTOR pathway, stimulate paracrine function and promote neovascularization by inhibiting PHD3 and stabilizing HIF-1α proteins in skeletal muscles. In contrast to many natural compounds, salidroside is water-soluble and highly bioavailable via oral administration and concentrated in urine by kidney excretion.

Summary

Rhodiola rosea extracts and salidroside can impose cellular and systemic benefits similar to the effect of positive lifestyle interventions to normal physiological functions and for anti-cancer. The unique pharmacological properties of Rhodiola rosea extracts or salidroside deserve further investigation for cancer chemoprevention, in particular for human urinary bladder cancer.

Different effects of feeding pregnant and lactating mice Rhodiola kirilowii aqueous and hydro-alcoholic extracts on their serum angiogenic activity and content of selected polyphenols

Angiogenesis plays an important role in many physiological processes, among them the formation of tissues and organs during embryogenesis. A lot of medicinal plants exhibit angiomodulatory properties. This creates the need for a thorough check of whether the plant extracts that we would like to give to pregnant women in order to increase their resistance to bacterial or viral infection will have negative effects on angiogenesis, and consequently on fetal development. This paper seeks to investigate the effect of serum of pregnant and nursing Balb/c mice that received aqueous (RKW) or hydro-alcoholic (RKW-A) R. kirilowii extracts (20 mg/kg), or epigallocatechin (0.2 mg/kg), on the in vitro proliferation and migration of mouse endothelial cell line Heca10. Of the 15 identified polyphenols in the extracts by HPLC, 8 were present in the sera. Chemical analysis revealed higher salidroside, kaempferol, chlorogenic acid, bFGF and VEGF concentration in RKW-A sera than in the sera of RKW group of mice. RKW-A and EGC sera did not affect migration of endothelial cells, however we noted some increase of migrating cells after RKW-sera treatment. RKW and EGC sera did not affect proliferation of endothelial cells. Sera of mothers from RKW-A group impaired the proliferation of endothelial cells in comparison to other groups. These data allow us to assume that Rhodiola kirilowii hydro-alcoholic extract (RKW-A) is potentially able to modulate pre- and post- natal angiogenesis what might influence the development of organs in progeny. Sera of RKW mothers have not harm the proliferation of endothelial cells, despite they also contain antiangiogenic catechins and salidroside. This suggests the existence in RKW-A extract and in RKW-A sera of some other, as yet unidentified substances influencing endothelial cells proliferation.

Immunomodulation on the ocular surface: a review

The increasing understanding of immune mechanisms changed our perception of the ocular surface, which is now considered a compartment of the common mucosal immune system. It offered the possibility to alter the physiological immune response on the ocular surface and effectively combat inflammation, which impairs stability of the tear film and causes tear hyperosmolarity, causing symptoms of dry eye disease. The paper provides an overview of ocular surface anatomy and physiology, explains the underlying mechanisms of dry eye disease and discusses novel and promising treatment modalities, such as cyclosporine A, biological therapies using autologous serum and various growth factors as well as experimental treatment methods which are currently being investigated.

Angiomodulatory properties of some antibiotics and Tołpa Peat Preparation

Deterioration of the immune system due to antibiotic therapy can be restored by immunomodulator application. In this paper we estimate the effect of ampicillin, amikacin, doxycycline, rifampicin, rifamycine and immunomodulator Tołpa Peat Preparation (TPP) on neovascular reaction induced in murine skin by human mononuclear cells (MNC) injection. MNC originating from 15 healthy volunteers were injected intradermally to Balb/c mice. Antibiotics (3, 15, or 75 mg/kg of body weight) alone or with TPP (10 mg/kg of body weight) were administrated subcutaneously to mice on three consecutive days. The number of newly formed blood vessels was measured in dissection microscope 72 hours after cell injection. Results: TPP stimulated angiogenic activity of MNC at the dose 5 and 10 mg/kg. Rifamycine exerted strong stimulatory action, ampicillin slightly stimulated immune response, while doxycycline and rifampicin downregulated it. Amikacin did not influence the results of angiogenesis tests. Studied antibiotics (15 mg/kg), except rifamycine, inhibit the angiostimulatory effect of the tested immunomodulator. TPP should be applied after antibiotic therapy to maintain its stimulatory effect and restore proper host immune function.

A natural herbal remedy modulates angiogenic activity of bronchoalveolar lavage cells from sarcoidosis patients

Sarcoidosis is a systemic inflammatory disease with abnormally high angiogenic activity of inflammatory cells. Reumaherb preparation consisting of three herbs: Echinacea purpurea, Harpagophytum procumbens, and Filipendula ulmaria, and it exerts anti-inflammatory, antioxidant, and analgesic activity and stimulates regenerative and immunological processes.

The aim of this paper was to estimate the effect of Reumaherb on immunological angiogenesis induced by bronchoalveolar lavage (BAL) cells collected from six patients with sarcoidosis and grafted into Balb/c mice skin. After grafting, the animals were fed for three days with 0.6 or 1.2 mg of Reumaherb (calculated from recommended human daily dose) daily, suspended in 40 µl of water, or 40 µl of water alone (control group).

A significant reduction of newly formed blood vessels was obtained in four cases for 1.2 mg and in three cases for 0.6 mg daily dose of this remedy. Thus, we hypothesise that Reumaherb promotes anti-angiogenic activity and may potentially be used in diseases associated with excessive blood vessel formation.