Carnosol inhibits cell adhesion molecules and chemokine expression by tumor necrosis factor-α in human umbilical vein endothelial cells through the nuclear factor-κB and mitogen-activated protein kinase pathways

Prospects of compounds of herbal plants as anticancer agents: a comprehensive review from molecular pathways

Cancer refers to the proliferation and multiplication of aberrant cells inside the human body, characterized by their capacity to proliferate and infiltrate various anatomical regions. Numerous biochemical pathways and signaling molecules have an impact on the cancer auto biogenesis process. The regulation of crucial cellular processes necessary for cell survival and proliferation, which are triggered by phytochemicals, is significantly influenced by signaling pathways. These pathways or components are regulated by phytochemicals. Medicinal plants are a significant reservoir of diverse anticancer medications employed in chemotherapy. The anticancer effects of phytochemicals are mediated by several methods, including induction of apoptosis, cessation of the cell cycle, inhibition of kinases, and prevention of carcinogenic substances. This paper analyzes the phytochemistry of seven prominent plant constituents, namely, alkaloids, tannins, flavonoids, phenols, steroids, terpenoids, and saponins, focusing on the involvement of the MAPK/ERK pathway, TNF signaling, death receptors, p53, p38, and actin dynamics. Hence, this review has examined a range of phytochemicals, encompassing their structural characteristics and potential anticancer mechanisms. It has underscored the significance of plant-derived bioactive compounds in the prevention of cancer, utilizing diverse molecular pathways. In addition, this endeavor also seeks to incentivize scientists to carry out clinical trials on anticancer medications derived from plants.

Carnosol prevents cardiac remodeling and ventricular arrhythmias in pressure overload-induced heart failure mice

Cardiac remodeling is a commonly observed pathophysiological phenomenon associated with the progression of heart failure in various cardiovascular disorders. Carnosol, a phenolic compound extracted from rosemary, possesses noteworthy pharmacological properties including anti-inflammatory, antioxidant, and anti-apoptotic activities. Considering the pivotal involvement of inflammation, oxidative stress, and apoptosis in cardiac remodeling, the present study aims to assess the effects of carnosol on cardiac remodeling and elucidate the underlying mechanisms. In an in vivo model, cardiac remodeling was induced by performing transverse aortic constriction (TAC) surgery on mice, while an in vitro model was established by treating neonatal rat cardiomyocytes (NRCMs) with Ang II. Our results revealed that carnosol treatment effectively ameliorated TAC-induced myocardial hypertrophy and fibrosis, thereby attenuating cardiac dysfunction in mice. Moreover, carnosol improved cardiac electrical remodeling and restored connexin 43 expression, thereby reducing the vulnerability to ventricular fibrillation (VF). Furthermore, carnosol significantly reduced Ang II-induced cardiomyocyte hypertrophy in NRCMs and alleviated the upregulation of hypertrophy and fibrosis markers. Both in vivo and in vitro models of cardiac remodeling exhibited the anti-inflammatory, anti-oxidative, and anti-apoptotic effects of carnosol. Mechanistically, these effects were mediated through the Sirt1/PI3K/AKT pathway, as the protective effects of carnosol were abrogated upon inhibition of Sirt1 or activation of the PI3K/AKT pathway. In summary, our study suggests that carnosol prevents cardiac structural and electrical remodeling by regulating the anti-inflammatory, anti-oxidative, and anti-apoptotic effects mediated by Sirt1/PI3K/AKT signaling pathways, thereby alleviating heart failure and VF.

Palliative effects of carnosol on lung-deposited pollutant particles-induced thrombogenicity and vascular injury in mice

The toxicity of inhaled particulate air pollution perseveres even at lower concentrations than those of the existing air quality limit. Therefore, the identification of safe and effective measures against pollutant particles-induced vascular toxicity is warranted. Carnosol is a bioactive phenolic diterpene found in rosemary herb, with anti-inflammatory and antioxidant actions. However, its possible protective effect on the thrombotic and vascular injury induced by diesel exhaust particles (DEP) has not been studied before. We assessed here the potential alleviating effect of carnosol (20 mg/kg) administered intraperitoneally 1 h before intratracheal (i.t.) instillation of DEP (20 μg/mouse). Twenty-four hours after the administration of DEP, various parameters were assessed. Carnosol administration prevented the increase in the plasma concentrations of C-reactive protein, fibrinogen, and tissue factor induced by DEP exposure. Carnosol inhibited DEP-induced prothrombotic effects in pial microvessels in vivo and platelet aggregation in vitro. The shortening of activated partial thromboplastin time and prothrombin time induced by DEP was abated by carnosol administration. Carnosol inhibited the increase in pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor α) and adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin) in aortic tissue. Moreover, it averted the effects of DEP-induced increase of thiobarbituric acid reactive substances, depletion of antioxidants and DNA damage in the aortic tissue. Likewise, carnosol prevented the decrease in the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) caused by DEP. We conclude that carnosol alleviates DEP-induced thrombogenicity and vascular inflammation, oxidative damage, and DNA injury through Nrf2 and HO-1 activation.

Carnosol ameliorated cancer cachexia-associated myotube atrophy by targeting P5CS and its downstream pathways

Introduction: Carnosol exhibited ameliorating effects on muscle atrophy of mice developed cancer cachexia in our previous research. Method: Here, the ameliorating effects of carnosol on the C2C12 myotube atrophy result from simulated cancer cachexia injury, the conditioned medium of the C26 tumor cells or the LLC tumor cells, were observed. To clarify the mechanisms of carnosol, the possible direct target proteins of carnosol were searched using DARTS (drug affinity responsive target stability) assay and then confirmed using CETSA (cellular thermal shift assay). Furthermore, proteomic analysis was used to search its possible indirect target proteins by comparing the protein expression profiles of C2C12 myotubes under treatment of C26 medium, with or without the presence of carnosol. The signal network between the direct and indirect target proteins of carnosol was then constructed. Results: Our results showed that, Delta-1-pyrroline-5-carboxylate synthase (P5CS) might be the direct target protein of carnosol in myotubes. The influence of carnosol on amino acid metabolism downstream of P5CS was confirmed. Carnosol could upregulate the expression of proteins related to glutathione metabolism, anti-oxidant system, and heat shock response. Knockdown of P5CS could also ameliorate myotube atrophy and further enhance the ameliorating effects of carnosol. Discussion: These results suggested that carnosol might ameliorate cancer cachexia-associated myotube atrophy by targeting P5CS and its downstream pathways.

Carnosol attenuates bleomycin-induced lung damage via suppressing fibrosis, oxidative stress and inflammation in rats

AIMS

Bleomycin, an important toxic anti-cancer agent, induces pulmonary fibrosis. The significance of oxidative stress and inflammation in promoting of bleomycin-induced idiopathic pulmonary fibrosis (IPF) has been reported. Thus, we evaluated the protective effects of carnosol as a robust natural antioxidant and anti-inflammatory agent for bleomycin-related IPF in rats.

MAIN METHODS

Male Wistar rats (n = 40) were randomly assigned to five groups. Group 1 was administrated with saline (intratracheally) on day 7 and oral gavage of dimethyl sulfoxide (DMSO, 0.05%) from day 1 to day 28. Group 2 received a single dose of bleomycin (intratracheally, 7.5 UI/kg) on day 7 and oral gavage of saline for 28 days. Groups 3, 4 and 5 were administrated with bleomycin (single dose) on day 7, along with oral administration of carnosol (at doses 10, 20 and 40 mg/kg, respectively) from day 1 to day 28. The lungs were isolated to measure the histopathological and biochemical and inflammatory markers.

KEY FINDINGS

Carnosol treatment significantly reduced malondialdehyde, nitric oxide, protein carbonyl, tumor necrosis factor- α, interleukin-6 levels and myeloperoxidase activity in the lungs of rats exposed to bleomycin. Also, lung glutathione content, catalase, glutathione peroxidase and superoxide dismutase activities significantly increased in the carnosol/bleomycin-treated group than the bleomycin group. Lung index, hydroxyproline content, fibrosis and histopathological changes, also significantly decreased by carnosol therapy.

SIGNIFICANCE

Treatment with carnosol can modulate biochemical and histological alterations caused by bleomycin. Thus, it can be regarded as an appropriate therapeutic approach for IPF.

Carnosol and its analogues attenuate muscle atrophy and fat lipolysis induced by cancer cachexia

BACKGROUND

Cancer cachexia is a multifactorial debilitating syndrome that directly accounts for more than 20% of cancer deaths while there is no effective therapeutic approach for treatment of cancer cachexia. Carnosol (CS) is a bioactive diterpene compound present in Lamiaceae spp., which has been demonstrated to have antioxidant, anti-inflammatory, and anticancer properties. But its effects on cancer cachexia and the possible mechanism remain a mystery.

METHODS

The in vitro cell models of C2C12 myotube atrophy and 3T3-L1 mature adipocyte lipolysis were used to check the activities of CS and its synthesized analogues. C26 tumour-bearing BALB/c mice were applied as the animal model to examine their therapeutic effects on cancer cachexia in vivo. Levels of related signal proteins in both in vitro and in vivo experiments were examined using western blotting to study the possible mechanisms.

RESULTS

Carnosol and its analogues [dimethyl-carnosol (DCS) and dimethyl-carnosol-D6 (DCSD)] alleviated myotube atrophy of C2C12 myotubes and lipolysis of 3T3-L1 adipocytes in vitro. Interestingly, CS and its analogues exhibited stronger inhibitive effects on muscle atrophy induced by tumour necrosis factor-α (TNF-α) (CS, P < 0.001; DCS, P < 0.001; DCSD, P < 0.001) in C2C12 myoblasts than on muscle atrophy induced by IL-6 (CS, P < 0.05; DCS, P = 0.08; DCSD, P < 0.05). In a C26 tumour-bearing mice model, administration of CS or its analogue DCSD significantly prevented body weight loss without affecting tumour size. At the end of the experiment, the body weight of mice treated with CS and DCSD was significantly increased by 11.09% (P < 0.01) and 11.38% (P < 0.01) compared with that of the C26 model group. CS and DCSD also improved the weight loss of epididymal adipose tissue in C26 model mice by 176.6% (P < 0.01) and 48.2% (P < 0.05) increase, respectively. CS and DCSD treatment partly preserved gastrocnemius myofibres cross-sectional area. CS treatment decreased the serum level of TNF-α (-95.02%, P < 0.01) but not IL-6 in C26 tumour-bearing mice. Inhibition on NF-κB and activation of Akt signalling pathway were involved in the ameliorating effects of CS and its analogues on muscle wasting both in vitro and in vivo. CS and its analogues also alleviated adipose tissue loss by inhibiting NF-κB and AMPK signalling pathways both in vitro and in vivo.

CONCLUSIONS

CS and its analogues exhibited anticachexia effects mainly by inhibiting TNF-α/NF-κB pathway and decreasing muscle and adipose tissue loss. CS and its analogues might be promising drug candidates for the treatment of cancer cachexia.

Carnosol as a Nrf2 Activator Improves Endothelial Barrier Function Through Antioxidative Mechanisms

Oxidative stress is the main pathogenesis of diabetic microangiopathy, which can cause microvascular endothelial cell damage and destroy vascular barrier. In this study, it is found that carnosol protects human microvascular endothelial cells (HMVEC) through antioxidative mechanisms. First, we measured the antioxidant activity of carnosol. We showed that carnosol pretreatment suppressed tert-butyl hydroperoxide (t-BHP)-induced cell viability, affected the production of lactate dehydrogenase (LDH) as well as reactive oxygen species (ROS), and increased the produce of nitric oxide (NO). Additionally, carnosol promotes the protein expression of vascular endothelial cadherin (VE-cadherin) to keep the integrity of intercellular junctions, which indicated that it protected microvascular barrier in oxidative stress. Meanwhile, we investigated that carnosol can interrupt Nrf2-Keap1 protein−protein interaction and stimulated antioxidant-responsive element (ARE)-driven luciferase activity in vitro. Mechanistically, we showed that carnosol promotes the expression of heme oxygenase 1(HO-1) and nuclear factor-erythroid 2 related factor 2(Nrf2). It can also promote the expression of endothelial nitric oxide synthase (eNOS). Collectively, our data support the notion that carnosol is a protective agent in HMVECs and has the potential for therapeutic use in the treatments of microvascular endothelial cell injury.

Inhibitory effect of Carnosol on UVB-induced inflammation via inhibition of STAT3

Ultraviolet B (UVB) irradiation causes sunburn, inflammatory responses, dysregulation of immune function, oxidative stress, DNA damage and photocarcinogenesis on skin. Rosemary (Rosmarinus officinalis L.) has been reported to inhibit inflammation. Carnosol, a major component of Rosemary, has prominent anti-inflammatory effects. However, its protective effect on UVB-induced inflammatory skin responses has not yet been reported. Here, we investigated the effectiveness of carnosol on UVB-induced inflammation. We examined the anti-inflammation effect of topical application of carnosol (0.05 µg/cm²) on UVB (540 mJ/cm², for 3 successive days)-induced skin inflammation in HR1 mice. Topical application of carnosol inhibited UVB-induced erythema, epidermal thickness, inflammatory responses in HR1 mice. Carnosol reduced the level of Immunoglobulin-E and IL-1β in blood serum of UVB-induced mice. Carnosol also significantly inhibited the UVB-induced expression of inflammatory marker protein (iNOS and COX-2) in back skin of mice. In addition, carnosol treated skin decreased activation of STAT3, a transcriptional factor regulating inflammatory genes. Our study suggested that carnosol has protective effects on skin inflammatory skin damages by UVB.

Combination chemotherapy with Zyflamend reduced the acquired resistance of bladder cancer cells to cisplatin through inhibiting NFκB signaling pathway

Background

Cisplatin-based chemotherapy is mainstay treatment in urinary bladder cancer (UBC). However, tumor recurrence frequently occurs with the acquisition of cisplatin resistance. We explored the potential effect of a polyherbal preparation, Zyflamend, on UBC cells resistant to cisplatin treatment.

Methods

To establish a cisplatin-resistant human bladder cancer cell line, T24 cells were cultured in increasing concentrations of cisplatin for more than 10 months. These cells (T24R) were then treated with different concentrations of Zyflamend, and both proliferation and activity of nuclear factor kappaB (NFκB) signaling pathway were examined. To test the synergistic effect between Zyflamend and cisplatin, we treated T24R cells either with Zyflamend or cisplatin alone, or in combination. Apoptotic effect was evaluated by Annexin V/propidium iodide double staining, and the levels of the proteins involved in cell cycle and anti-apoptosis were examined by Western blotting. Finally, mice with palpable xenograft were treated either with cisplatin and Zyflamend alone or in combination for 28 days before they were sacrificed for measuring the sizes and weights of the tumor tissues. In addition, proliferation and apoptosis markers were examined by immunohistochemistry.

Results

Comparing to that in the parental T24 cells, NFκB is constitutively active in cisplatin-resistant T24R cells. Zyflamend is capable of inhibiting the growth of T24, T24R, as well as another UBC cell line J82 in a concentration-dependent manner. Mechanistically, Zyflamend suppresses NFκB-mediated cell proliferation, survival, and invasion/angiogenesis and induces apoptosis. In addition, Zyflamend significantly increased the sensitivity of T24R and J82 cells to cisplatin treatment and these findings were confirmed in T24R xenograft model with reduced proliferation index and decreased expression of RelA and its downstream target MMP9.

Conclusion

Zyflamend is capable of counteracting bladder cancer resistance to cisplatin by repressing proliferation and inducing apoptosis through targeting NFκB signaling pathway.

Inhibitory Effect of Carnosol on Phthalic Anhydride-Induced Atopic Dermatitis via Inhibition of STAT3

Carnosol is a phenolic antioxidant present in rosemary (Rosmarinus officinalis). It is known for anti-inflammatory effects, analgesic activity and anti-cancer effects. However, no study has been dedicated yet to its effect on atopic dermatitis (AD). Here, we show that carnosol effectively inhibited LPS-induced nitric oxide (NO) generation and expression of inflammatory marker proteins (iNOS and COX-2) in RAW 264.7 cells. In addition, carnosol effectively inhibits the phosphorylation of STAT3 and DNA binding activity in RAW 264.7 cells. Pull down assay and docking model analysis showed that carnosol directly binds to the DNA binding domain (DBD) of STAT3. We next examined the anti-atopic activity of carnosol (0.05 µg/cm²) using 5% Phthalic anhydride (PA)-induced AD model in HR1 mice. Carnosol treatment significantly reduced 5% PA-induced AD like skin inflammation in skin tissues compared with control mice. Moreover, carnosol treatment inhibits the expression of iNOS and COX-2 in skin tissue. In addition, the levels of TNF-α, IL-1β, and Immunoglobulin-E in blood serum was significantly decreased in carnosol treated mice compared with those of 5% PA treated group. Furthermore, the activation of STAT3 in skin tissue was decreased in carnosol treated mice compared with control mice. In conclusion, these findings suggest that carnosol exhibited a potential anti-AD activity by inhibiting pro-inflammatory mediators through suppression of STAT3 activation via direct binding to DBD of STAT3.

Differential activation of pregnane X receptor by carnosic acid, carnosol, ursolic acid, and rosmarinic acid

Pregnane X receptor (PXR) regulates the expression of many genes, including those involved in drug metabolism and transport, and has been linked to various diseases, including inflammatory bowel disease. In the present study, we determined whether carnosic acid and other chemicals in rosemary extract (carnosol, ursolic acid, and rosmarinic acid) are PXR activators. As assessed in dual-luciferase reporter gene assays, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, activated human PXR (hPXR) and mouse PXR (mPXR), whereas carnosol and ursolic acid, but not carnosic acid or rosmarinic acid, activated rat PXR (rPXR). Dose-response experiments indicated that carnosic acid, carnosol, and ursolic acid activated hPXR with EC50 values of 0.79, 2.22, and 10.77μM, respectively. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, transactivated the ligand-binding domain of hPXR and recruited steroid receptor coactivator-1 (SRC-1), SRC-2, and SRC-3 to the ligand-binding domain of hPXR. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, increased hPXR target gene expression, as shown by an increase in CYP3A4, UGT1A3, and ABCB1 mRNA expression in LS180 human colon adenocarcinoma cells. Rosmarinic acid did not attenuate the extent of hPXR activation by rifampicin, suggesting it is not an antagonist of hPXR. Overall, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, are hPXR agonists, and carnosic acid shows species-dependent activation of hPXR and mPXR, but not rPXR. The findings provide new mechanistic insight on the effects of carnosic acid, carnosol, and ursolic acid on PXR-mediated biological effects.

Natural product HTP screening for antibacterial (E.coli 0157:H7) and anti-inflammatory agents in (LPS from E. coli O111:B4) activated macrophages and microglial cells; focus on sepsis

Background

Acute systemic inflammatory response syndrome arising from infection can lead to multiple organ failure and death, with greater susceptibility occurring in immunocompromised individuals. Moreover, sub-acute chronic inflammation is a contributor to the pathology of diverse degenerative diseases (Parkinson’s disease, Alzheimer’s disease and arthritis). Given the known limitations in Western medicine to treat a broad range of inflammatory related illness as well as the emergence of antibiotic resistance, there is a renewed interest in complementary and alternative medicines (CAMs) to achieve these means.

Methods

A high throughput (HTP) screening of >1400 commonly sold natural products (bulk herbs, cooking spices, teas, leaves, supplement components, nutraceutical food components, fruit and vegetables, rinds, seeds, polyphenolics etc.) was conducted to elucidate anti-inflammatory substances in lipopolysaccharide (LPS) (E. coli serotype O111:B4) monocytes: RAW 264.7 macrophages [peripheral], BV-2 microglia [brain]) relative to hydrocortisone, dexamethasone and L-N6-(1Iminoethyl)lysine (L-NIL). HTP evaluation was also carried out for lethal kill curves against E.coli 0157:H7 1x10⁶ CFU/mL relative to penicillin. Validation studies were performed to assess cytokine profiling using antibody arrays. Findings were corroborated by independent ELISAs and NO2–/iNOS expression quantified using the Griess Reagent and immunocytochemistry, respectively. For robust screening, we developed an in-vitro efficacy paradigm to ensure anti-inflammatory parameters were observed independent of cytotoxicity. This caution was taken given that many plants exert tumoricidal and anti-inflammatory effects at close range through similar signaling pathways, which could lead to false positives.

Results

The data show that activated BV-2 microglia cells (+ LPS 1μg/ml) release >10-fold greater IL-6, MIP1/2, RANTES and nitric oxide (NO2–), where RAW 264.7 macrophages (+ LPS 1μg/ml) produced > 10-fold rise in sTNFR2, MCP-1, IL-6, GCSF, RANTES and NO2–. Data validation studies establish hydrocortisone and dexamethasone as suppressing multiple pro-inflammatory processes, where L-NIL suppressed NO2–, but had no effect on iNOS expression or IL-6. The screening results demonstrate relative few valid hits with anti-inflammatory effects at < 250μg/ml for the following: Bay Leaf (Laurus nobilis), Elecampagne Root (Inula helenium), Tansy (Tanacetum vulgare),Yerba (Eriodictyon californicum) and Centipeda (Centipeda minima), Ashwagandha (Withania somnifera), Feverfew (Tanacetum parthenium), Rosemary (Rosmarinus officinalis), Turmeric Root (Curcuma Longa), Osha Root (Ligusticum porteri), Green Tea (Camellia sinensis) and constituents: cardamonin, apigenin, quercetin, biochanin A, eupatorin, (-)-epigallocatechin gallate (EGCG) and butein. Natural products lethal against [E. coli 0157:H7] where the LC₅₀ < 100 μg/ml included bioactive silver hydrosol-Argentyn 23, green tea (its constituents EGCG > Polyphenon 60 > (-)-Gallocatechin > Epicatechin > (+)-Catechin), Grapeseed Extract (Vitis vinifera), Chinese Gallnut (its constituents gallic acid > caffeic acid) and gallic acid containing plants such as Babul Chall Bark (Acacia Arabica), Arjun (Terminalia Arjuna) and Bayberry Root Bark (Morella Cerifera).

Conclusions

These findings emphasize and validate the previous work of others and identify the most effective CAM anti-inflammatory, antibacterial compounds using these models. Future work will be required to evaluate potential combination strategies for long-term use to prevent chronic inflammation and possibly lower the risk of sepsis in immunocompromised at risk populations.

Carnosol and Related Substances Modulate Chemokine and Cytokine Production in Macrophages and Chondrocytes

Phenolic diterpenes present in Rosmarinus officinalis and Salvia officinalis have anti-inflammatory and chemoprotective effects. We investigated the in vitro effects of carnosol (CL), carnosic acid (CA), carnosic acid-12-methylether (CAME), 20-deoxocarnosol and abieta-8,11,13-triene-11,12,20-triol (ABTT) in murine macrophages (RAW264.7 cells) and human chondrocytes. The substances concentration-dependently reduced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in LPS-stimulated macrophages (i.e., acute inflammation). They significantly blunted gene expression levels of iNOS, cytokines/interleukins (IL-1α, IL-6) and chemokines including CCL5/RANTES, CXCL10/IP-10. The substances modulated the expression of catabolic and anabolic genes in chondrosarcoma cell line SW1353 and in primary human chondrocytes that were stimulated by IL-1β (i.e., chronic inflammation In SW1353, catabolic genes like MMP-13 and ADAMTS-4 that contribute to cartilage erosion were down-regulated, while expression of anabolic genes including Col2A1 and aggrecan were shifted towards pre-pathophysiological homeostasis. CL had the strongest overall effect on inflammatory mediators, as well as on macrophage and chondrocyte gene expression. Conversely, CAME mainly affected catabolic gene expression, whereas ABTT had a more selectively altered interleukin and chemokine gene exprssion. CL inhibited the IL-1β induced nuclear translocation of NF-κBp65, suggesting that it primarily regulated via the NF-κB signalling pathway. Collectively, CL had the strongest effects on inflammatory mediators and chondrocyte gene expression. The data show that the phenolic diterpenes altered activity pattern of genes that regulate acute and chronic inflammatory processes. Since the substances affected catabolic and anabolic gene expression in cartilage cells in vitro, they may beneficially act on the aetiology of osteoarthritis.

The Therapeutic Potential of Rosemary (Rosmarinus officinalis) Diterpenes for Alzheimer's Disease

Rosemary (Rosmarinus officinalis L.) is one of the most economically important species of the family Lamiaceae. Native to the Mediterranean region, the plant is now widely distributed all over the world mainly due to its culinary, medicinal, and commercial uses including in the fragrance and food industries. Among the most important group of compounds isolated from the plant are the abietane-type phenolic diterpenes that account for most of the antioxidant and many pharmacological activities of the plant. Rosemary diterpenes have also been shown in recent years to inhibit neuronal cell death induced by a variety of agents both in vitro and in vivo. The therapeutic potential of these compounds for Alzheimer's disease (AD) is reviewed in this communication by giving special attention to the chemistry of the compounds along with the various pharmacological targets of the disease. The multifunctional nature of the compounds from the general antioxidant-mediated neuronal protection to other specific mechanisms including brain inflammation and amyloid beta (Aβ) formation, polymerisation, and pathologies is discussed.