Browsing by Author "Sen, Alaattin"

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Amelioration potential of synthetic oxime chemical cores against multiple sclerosis and Alzheimer's diseases: Evaluation in aspects of in silico and in vitro experiments
(ELSEVIER, 2024) Yilmaz, Anil; Koca, Murat; Ercan, Selami; Acar, Ozden Ozgun; Boga, Mehmet; Sen, Alaattin; Kurt, Adnan; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Sen, Alaattin
Alzheimer disease (AD) and multiple sclerosis (MS) are inflammatory neurological disorders. The main symptom of AD is dementia, and the main symptoms of MS are vertigo, sexual dysfunction, cognitive problems, and fatigue. Today, millions of people are affected by AD and MS, and the number is growing day by day. However, there are not any accurate remedies for both disorders. For this reason, discovering novel drug molecules against neurological disorders such as AD and MS is essential and precious. Oximes and benzofurans exhibit many pharmacological effects including anti-inflammatory and neurological activities. Thus, several novel compounds bearing oxime and benzofuran chemical cores were designed and synthesized, and their in vitro anticholinesterase activities were investigated in our previous study. A number of the synthesized molecules showed excellent anticholinesterase activity against both AChE and BChE enzymes. The mentioned study constituted a background for this study. In this study, we picked different chemical skeletons among all the synthesized molecules to conduct further in silico and in vitro experiments. In order to support our in vitro anticholinesterase findings, we also examined in silico anti-Alzheimer activity of the selected molecules. In addition, in silico and in vitro activities against MS disease of the synthesized molecules were investigated. Molecule 4 extraordinarily showed outstanding activity against AD disease both in silico and in vitro, as well as in silico activity against MS disease. This feature makes molecule 4 a possible drug lead molecule which is very limited in the market. On the other hand, molecule 1, a less substituted oxime skeleton, demonstrated the strongest in vitro activity against MS disease through in vitro anti-inflammatory effect. As an observation, molecule 4 was determined to be the most promising molecule to focus on in the further steps.
Apatinib Sensitizes Human Breast Cancer Cells against Navitoclax and Venetoclax Despite Up-regulated Bcl-2 and Mcl-1 Gene Expressions
(KARE PUBLCONCORD ISTANBUL, DUMLUPINAR MAH, CIHAN SK NO 15, B BLOK 162 KADIKOY, ISTANBUL, TURKEY, 2021) Kavakcioglu Yardimci, Berna; Ozgun Acar, Ozden; Semiz, Asli; Sen, Alaattin; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Sen, Alaattin
OBJECTIVE Defects in apoptotic cell death which restrict the success of conventional cytotoxic therapies have pivotal roles in a number of pathological conditions including cancer. However, a novel drug class targeting pro-survival Bcl-2 protein family members has been developed with the understanding of the structures and interactions of Bcl-2 proteins. Within this new class, Bcl-2/Bcl-xL inhibitor Navitoclax and Bcl-2 specific inhibitor Venetoclax have been shown to demonstrate strong anticancer activities on several types of cancers. But their low affinity to other anti-apoptotic proteins limits their clinical usage. Here, we investigated the cytotoxic and apoptotic effects of Navitoclax/Venetoclax and their combinations with specific tyrosine kinase inhibitor Apatinib on estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 breast cancer cell lines. METHODS MTT assay was used for the evaluation of the inhibition of cancer cell proliferation. ELISA test and Quantitative real-time PCR assay was performed to determine the role of caspase-3, Bak, Bax, Bcl-2, Bcl-xL and Mcl-1 proteins in the inhibition of cell proliferation triggered by the tested agents. RESULTS We found that aggressive MDA-MB-231 cell line was more sensitive to all tested agents. Apatinib significantly enhanced Navitoclax/Venetoclax mediated inhibition of cell viability in both cancer cell lines despite up-regulation in the expression levels of Bcl-2 and Mcl-1 genes. We further demonstrated significant Bak/Bax and caspase-3 expression in less aggressive MCF-7 cells. CONCLUSION Our findings have impacts on Navitoclax/Venetoclax plus Apatinib based therapy for breast adenocarcinoma. On the other hand, further studies should be conducted to elucidate the mechanisms underlying synergistic effects of Navitoclax/Venetoclax plus Apatinib combinations.
Biochemical, pharmacological, and toxicological attributes of caper (Capparis ovata) flowering buds and berries pickles
(WILEY, 2022) Ozgun-Acar, Ozden; Celik-Turgut, Gurbet; Guner, Huseyin; Sezer, Serdar; Sen, Alaattin; 0000-0002-8444-376X; 0000-0002-0220-5224; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Güner, Hüseyin; Şen, Alaattin
Capparis ovata is a natural plant that grows widely in Turkey and its flowering buds and berry pickle are used in traditional medicine. Thus, the current study was expanded to evaluate the biochemical, pharmacological, and toxicological aspects of the Capparis ovata water extract (COWE). To determine the biochemical properties of COWE, mineral and fatty acid content, elemental analysis, flavonoid/phenolic content, radicalscavenging capacity, and pesticide analysis were performed. Furthermore, to find out whether it had anti-inflammatory properties, reverse transcription-polymerase chain reaction (RT-PCR) and nuclear factor kappa B (NF-κB) luciferase activity tests were conducted. Whole-genome transcriptomic profiling was carried out at a dose level of 500 mg/kg COWE to understand its pharmacological effect. Transaminases in serum were tested, and quantitative polymerase chain reaction (qPCR) was done using a custom design array that included the stress and molecular toxicology pathway to establish its toxicological qualities. As a result of the evaluations, it was observed that COWE has a high mineral and unsaturated fatty acid content, flavonoid/phenolic content, and radical-scavenging ability. It significantly inhibited NF-κB transcriptional activity as well as inflammatory cytokine expression in T-lymphoblast cells. Wholegenome transcriptomic profiling depicted that COWE modulates immune responses by upregulating natural killer cell activation, cellular response to type I interferon, B-cell proliferation and differentiation, and Janus kinase–signal transducer and activator of transcription (JAK–STAT) pathways. Molecular Toxicology Pathfinder RT2 Profiler PCR array analysis revealed that COWE at or lower dose of 500 mg/kg/day did not cause a comparatively adverse effect. According to the findings, COWE is a rich source of nutrients and can be used as an adjunct therapy for various inflammatory diseases
Cerium Oxide Nanoparticles Biosynthesized Using Fresh Green Walnut Shell in Microwave Environment and their Anticancer Effect on Breast Cancer Cells
(John Wiley and Sons Inc, 2022) Sulak, Mine; Turgut, Gurbet Celik; Sen, Alaattin; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Sen, Alaattin
In this study, cerium oxide nanoparticles (CONPs) were synthesized using fresh green walnut shell extract in microwave environment. The morphology and structure of the CONPs were determined using ultraviolet-visible (UV/VIS), attenuated total reflection-Fourier transform infrared (ATR-FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). Crystal purple staining, Annexin V-FITC detection, RT-PCR, P53, and NF-κB luciferase reporter assays were performed to evaluate the mechanism of action of CONPs in breast cancer cell lines (MCF7). The biosynthesized CONPs showed cytotoxic effects and induced apoptosis in MCF7 cells. Furthermore, CONPs induced P53 expression and suppressed NF-κB gene expression, both of which were confirmed using reporter assays. Based on the present results, it was concluded that CONPs can induce apoptosis by acting on P53 at the transcriptional level and may cause cell death by suppressing NF-κB-mediated transcription.
Evaluation of Anti-Alzheimer Activity of Synthetic Coumarins by Combination of in Vitro and in Silico Approaches
(John Wiley and Sons Inc, 2022) Erdogan Orhan, Ilkay; Deniz, F. Sezer Senol; Salmas, Ramin Ekhteiari; Irmak, Sule; Acar, Ozden Ozgun; Turgut, Gurbet Celik; Sen, Alaattin; Zbancioc, Ana-Maria; Luca, Simon Vlad; Skalicka-Woźniak, Krystyna; Skiba, Adrianna; Tataringa, Gabriela; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Sen, Alaattin
Series of synthetic coumarin derivatives (1-16) were tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), two enzymes linked to the pathology of Alzheimer's disease (AD). Compound 16 was the most active AChE inhibitor with IC50 32.23±2.91 μM, while the reference (galantamine) had IC50=1.85±0.12 μM. Compounds 9 (IC5075.14±1.82 μM), 13 (IC50=16.14±0.43 μM), were determined to be stronger BChE inhibitors than the reference galantamine (IC50=93.53±2.23 μM). The IC50 value of compound 16 for BChE inhibition (IC50=126.56±11.96 μM) was slightly higher than galantamine. The atomic interactions between the ligands and the key amino acids inside the binding cavities were simulated to determine their ligand-binding positions and free energies. The three inhibitory coumarins (9, 13, 16) were next tested for their effects on the genes associated with AD using human neuroblastoma (SH-SY5Y) cell lines. Our data indicate that they could be considered for further evaluation as new anti-Alzheimer drug candidates.
Natural diterpenoid alysine A isolated from Teucrium alyssifolium exerts antidiabetic effect via enhanced glucose uptake and suppressed glucose absorption
(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, ATATURK BULVARI NO 221, KAVAKLIDERE, TR-06100 ANKARA, TURKEY, 2019) Sen, Alaattin; Ayar, Buket; Yilmaz, Anil; Acar, Ozden Ozgun; Turgut, Gurbet Celik; Topcu, Gulacti; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü;
Teucrium species have been used in folk medicine as antidiabetic, antiinflammatory, antiulcer, and antibacterial agents. We have explored in vitro antidiabetic impacts of 2 natural diterpenoids, alysine A and alysine B, isolated from Teucrium alyssifolium. The lactate dehydrogenase (LDH) cytotoxicity assay, glucose uptake test, glucose utilization (glycogen content) test, glucose transport test, glucose absorption (a-glucosidase activity) test, insulin secretion test, RNA isolation and cDNA synthesis assay, qPCR quantification assays, and statistical analyses were carried out in the present study. Alysine A exerted the following effects at non-cytotoxic doses: Enhanced the glucose uptake, as much as the insulin in the C2C12, HepG2, and 3T3-L1 cells Increased the glycogen content in the C2C12 and HepG2 liver cells, significantly higher than the insulin and metformin Suppressed the alpha-glucosidase and the GLUT2 expression levels in the Caco-2 cells Suppressed the SGLT1 and GLUT1-5 expression levels in the Caco-2 cells Induced the insulin receptor substrate (IRS)1 and GLUT2 expression levels of the BTC6 pancreatic cells Induced the insulin receptor (INSR), IRS2, phosphoinositide 3-kinase (PI3K), GLUT4, and protein kinase (PK) expression levels of the 3T3-L1 and C2C12 cells Increased glucose transport through the Caco-2 cell layer Did not influence insulin secretion in the pancreatic BTC6 cells Consequently, these data strongly emphasized the antidiabetic action of alysine A on the particularly critical model mechanisms that assume a part in glucose homeostasis, such as glucose uptake, utilization, and storage. Moreover, the expression level of the essential genes in glucose metabolism and insulin signaling was altered in a way that the results would be antihyperglycemic. A blend of in vitro and in situ tests affirmed the antihyperglycemic action of alysine A and its mechanism. Alysine A has exercised significant and positive results on the glucose homeostasis; thus, it is a natural and pleiotropic antidiabetic agent. Advanced in vivo studies are required to clarify the impact of this compound on glucose homeostasis completely.
Prophylactic and therapeutic roles of oleanolic acid and its derivatives in several diseases
(BAISHIDENG PUBLISHING GROUP INC, 7041 Koll Center Parkway, Suite 160, PLEASANTON, CA, UNITED STATES, 2020) Sen, Alaattin; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü
Oleanolic acid (OA) and its derivatives are widely found in diverse plants and are naturally effective pentacyclic triterpenoid compounds with broad prophylactic and therapeutic roles in various diseases such as ulcerative colitis, multiple sclerosis, metabolic disorders, diabetes, hepatitis and different cancers. This review assembles and presents the latestin vivoreports on the impacts of OA and OA derivatives from various plant sources and the biological mechanisms of OA activities. Thus, this review presents sufficient data proposing that OA and its derivatives are potential alternative and complementary therapies for the treatment and management of several diseases.
Role of AHR, NF-kB and CYP1A1 crosstalk with the X protein of Hepatitis B virus in hepatocellular carcinoma cells
(ELSEVIER, 2023) Celik-Turgut, Gurbet; Olmez, Nazmiye; Koc, Tugba; Ozgun-Acar, Ozden; Semiz, Asli; Dodurga, Yavuz; Satiroglu-Tufan, Naciye Lale; Sen, Alaattin; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Şen, Alaattin
In this study, it was aimed to elucidate the interaction between aryl hydrocarbon receptor (AHR), nuclear factor -kappa B (NF-kB), and cytochrome P4501A1 (CYP1A1) with hepatitis B virus X protein (HBX) in a human liver cancer cell line (HepG2) transfected with HBX. First, AHR, NF-kB, and CYP1A1 genes were cloned into the appropriate region of the CheckMate mammalian two-hybrid recipient plasmids using a flexi vector system. Renilla and firefly luciferases were quantified using the dual-luciferase reporter assay system to measure the interactions. Secondly, transient transfections of CYP1A1 and NF-kB (RelA) were performed into HBX-positive and HBX-negative HepG2 cells. The mRNA expression of CYP1A1 and NF-kB genes were confirmed with RT-PCR, and cell viability was measured by WST-1. Further verification was assessed by measuring the activity and protein level of CYP1A1. Additionally, CYP1A1/HBX protein-protein interactions were performed with co-immunoprecipitation, which demonstrated no interaction. These results have clearly shown that the NF-kB and AHR genes interact with HBX without involving CYP1A1 and HBX protein-protein interactions. The pre-sent study confirms that AHR and NF-kB interaction plays a role in the HBV mechanism mediated via HBX and coordinating the carcinogenic or inflammatory responses; still, the CYP1A1 gene has no effect on this interaction.
Role of cytochrome P450 polymorphisms and functions in development of ulcerative colitis
(BAISHIDENG PUBLISHING GROUP INC, 8226 REGENCY DR, PLEASANTON, CA 94588 USA, 2019) Sen, Alaattin; Stark, Holger; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü;
Cytochromes P450s (CYPs) are terminal enzymes in CYP dependent monooxygenases, which constitute a superfamily of enzymes catalysing the metabolism of both endogenous and exogenous substances. One of their main tasks is to facilitate the excretion of these substances and eliminate their toxicities in most phase 1 reactions. Endogenous substrates of CYPs include steroids, bile acids, eicosanoids, cholesterol, vitamin D and neurotransmitters. About 80% of currently used drugs and environmental chemicals comprise exogenous substrates for CYPs. Genetic polymorphisms of CYPs may affect the enzyme functions and have been reported to be associated with various diseases and adverse drug reactions among different populations. In this review, we discuss the role of some critical CYP isoforms (CYP1A1, CYP2D6, CYP2J2, CYP2R1, CYP3A5, CYP3A7, CYP4F3, CYP24A1, CYP26B1 and CYP27B1) in the pathogenesis or aetiology of ulcerative colitis concerning gene polymorphisms. In addition, their significance in metabolism concerning ulcerative colitis in patients is also discussed showing a clear underestimation in genetic studies performed so far.
Suppression of inflammatory cytokines expression with bitter melon (Momordica charantia) in TNBS-instigated ulcerative colitis
(SCIENDO, BOGUMILA ZUGA 32A, WARSAW, MAZOVIA, POLAND, 2020) Acar, Ozden Ozgun; Cetin, Hulya; Semiz, Gurkan; Sen, Alaattin; 0000-0002-2910-6349; 0000-0002-2826-1021; 0000-0003-0276-8542; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü
Background and Objective: This study was aimed to elucidate the molecular mechanism of Momordica charantia (MCh), along with a standard drug prednisolone, in a rat model of colitis induced by trinitrobenzene sulfonic acid (TNBS). Methods: After the induction of the experimental colitis, the animals were treated with MCh (4 g/kg/day) for 14 consecutive days by intragastric gavage. The colonic tissue expression levels of C-C motif chemokine ligand 17 (CCL-17), interleukin (IL)-1 beta, IL-6, IL-23, interferon-gamma (IFN-gamma), nuclear factor kappa B (NFkB), and tumor necrosis factor-alpha (TNF-alpha), were determined at both mRNA and protein levels to estimate the effect of MCh. Besides, colonic specimens were analyzed histopathologically after staining with hematoxylin and eosin. Results: The body weights from TNBS-instigated colitis rats were found to be significantly lower than untreated animals. Also, the IFN-gamma, IL-1 beta, IL-6, Il-23, TNF-alpha, CCL-17, and NF-kB mRNA and protein levels were increased significantly from 1.86-4.91-fold and 1.46-5.50-fold, respectively, in the TNBS-instigated colitis group as compared to the control. Both the MCh and prednisolone treatment significantly reduced the bodyweight loss. It also restored the induced colonic tissue levels of IL-1 beta, IL-6, IFN-gamma, and TNF-alpha to normal levels seen in untreated animals. These results were also supported with the histochemical staining of the colonic tissues from both control and treated animals. Conclusion: The presented data strongly suggests that MCh has the anti-inflammatory effect that might be modulated through vitamin D metabolism. It is the right candidate for the treatment of UC as an alternative and complementary therapeutics.
Synthesis and Comprehensive in Vivo Activity Profiling of Olean-12-en-28-ol, 3β-Pentacosanoate in Experimental Autoimmune Encephalomyelitis: A Natural Remyelinating and Anti-Inflammatory Agent
(American Chemical Society(ACM), 2023) Senol, Halil; Ozgun-Acar, Ozden; Daǧ, Aydan; Eken, Ahmet; Guner, Hüseyin; Aykut, Zaliha Gamze; Topcu, Gulacti; Sen, Alaattin; 0000-0002-8444-376X; 0000-0002-0220-5224; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Sen, Alaattin; Güner, Hüseyin
Multiple sclerosis (MS) treatment has received much attention, yet there is still no certain cure. We herein investigate the therapeutic effect of olean-12-en-28-ol, 3β-pentacosanoate (OPCA) on a preclinical model of MS. First, OPCA was synthesized semisynthetically and characterized. Then, the mice with MOG35-55-induced experimental autoimmune/allergic encephalomyelitis (EAE) were given OPCA along with a reference drug (FTY720). Biochemical, cellular, and molecular analyses were performed in serum and brain tissues to measure anti-inflammatory and neuroprotective responses. OPCA treatment protected EAE-induced changes in mouse brains maintaining blood-brain barrier integrity and preventing inflammation. Moreover, the protein and mRNA levels of MS-related genes such as HLD-DR1, CCL5, TNF-α, IL6, and TGFB1 were significantly reduced in OPCA-treated mouse brains. Notably, the expression of genes, including PLP, MBP, and MAG, involved in the development and structure of myelin was significantly elevated in OPCA-treated EAE. Furthermore, therapeutic OPCA effects included a substantial reduction in pro-inflammatory cytokines in the serum of treated EAE animals. Lastly, following OPCA treatment, the promoter regions for most inflammatory regulators were hypermethylated. These data support that OPCA is a valuable and appealing candidate for human MS treatment since OPCA not only normalizes the pro- and anti-inflammatory immunological bias but also stimulates remyelination in EAE.
Synthesis of nitrogen-containing oleanolic acid derivatives as carbonic anhydrase and acetylcholinesterase inhibitors
(SPRINGER BIRKHAUSER, 2023) Senol, Halil; Turgut, Gurbet Celik; Sen, Alaattin; 0000-0002-8444-376X; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü; Sen, Alaattin
In this study, a total of 13 compounds (5-17) were synthesized starting from oleanolic acid (OA), a natural triterpenoid. Five new compounds (10, 11, 12, 15 and 17), are the main targets of the study, which were synthesized for the first time in this work as oxime, imine and hydrazone derivatives of OA. Other compounds were previously obtained as natural or semi-synthetically. NMR and HRMS analyses were carried out to determine of structures of all the synthesized molecules. The inhibitory effects of the synthesized compounds on acetylcholinesterase (AChE), human carbonic anhydrase I (hCA I) and II (hCA II) were evaluated. Compounds 13 and 15 showed better inhibitory activity than the other compounds against both hCA I and hCA II isoenzymes, which are competing with AZA. In addition, compound 15 showed the strongest AChE inhibitory activity among all the tested compounds, with an IC50 value of 34.46 mu M.
Triterpenoids and steroids isolated from Anatolian Capparis ovata and their activity on the expression of inflammatory cytokines
(TAYLOR & FRANCIS LTD, 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND, 2020) Gazioglu, Isil; Semen, Sevcan; Acar, Ozden Ozgun; Kolak, Ufuk; Sen, Alaattin; Topcu, Gulacti; 0000-0002-8444-376X; 0000-0002-7946-6545; 0000-0002-3283-1824; AGÜ, Yaşam ve Doğa Bilimleri Fakültesi, Moleküler Biyoloji ve Genetik Bölümü
Context CapparisL. (Capparaceae) is grown worldwide. Caper has been used in traditional medicine to treat various diseases including rheumatism, kidney, liver, stomach, as well as headache and toothache. Objective To isolate and elucidate of the secondary metabolites of theC. ovataextracts which are responsible for their anti-inflammatory activities. Materials and methods Buds, fruits, flowers, leaves and stems ofC. ovataDesf. was dried, cut to pieces, then ground separately. From their dichloromethane/hexane (1:1) extracts, eight compounds were isolated and their structures were elucidated by NMR, mass spectroscopic techniques. The effects of compounds on the expression of inflammatory cytokines in SH-SY5Y cell lines were examined by qRT-PCR ranging from 4 to 96 mu M. Cell viability was expressed as a percentage of the control, untreated cells. Results This is a first report on isolation of triterpenoids and steroids fromC. ovatawith anti-inflammatory activity. One new triterpenoid ester olean-12-en-3 beta,28-diol, 3 beta-pentacosanoate (1) and two new natural steroids 5 alpha,6 alpha-epoxycholestan-3 beta-ol (5) and 5 beta,6 beta-epoxycholestan-3 beta-ol (6) were elucidated besides known compounds; oleanolic acid (2), ursolic acid (3), beta-sitosterol (4), stigmast-5,22-dien-3 beta-myristate (7) and bismethyl-octylphthalate (8). mRNA expression levels as EC(10)of all the tested seven genes were decreased, particularly CXCL9 (19.36-fold), CXCL10 (8.14-fold), and TNF (18.69) by the treatment of 26 mu M of compound1on SH-SY5Y cells. Discussion and conclusions Triterpenoids and steroids isolated fromC. ovatawere found to be moderate-strong anti-inflammatory compounds. Particularly, compounds1and3were found to be promising therapeutic agents in the treatment of inflammatory and autoimmune diseases.