Exclusion of Polymorphisms in Carnosinase Genes (CNDP1 and CNDP2) as a Cause of Diabetic Nephropathy in Type 1 Diabetes: Results of Large Case-Control and Follow-Up Studies

OBJECTIVES— Recently, an association was found between diabetic nephropathy and the D18S880 microsatellite, located in the carnosinase gene (CNDP1) on chromosome 18q. Alleles of this microsatellite encode for a variable number of leucine residues (from four to seven) in the leader peptide of the carnosinase precursor. The frequency of subjects homozygous for the five leucines was higher in control subjects than in case subjects in studies focusing on type 2 diabetic patients. To test whether this finding can be extended to type 1 diabetic patients, we carried out a comprehensive study on association between diabetic nephropathy and the D18S880 microsatellite and 21 additional SNPs that tagged the genomic region containing CNDP1 and CNDP2

Clinical application of 1,5-anhydroglucitol measurements in patients with hepatocyte nuclear factor-1α maturity-onset diabetes of the young

OBJECTIVE - 1,5-anhydroglucitol (1,5-AG) is a short-term marker of metabolic control in diabetes. Its renal loss is stimulated in hyperglycemic conditions by glycosuria, which results in a lowered plasma concentration. As a low renal threshold for glucose has been described in hepatocyte nuclear factor-1α (HNF-1α) maturity-onset diabetes of the young (MODY), the 1,5-AG level may be altered in these patients. The purpose of this study was to assess the 1,5-AG levels in patients with HNF-1α MODY and in type 2 diabetic subjects with a similar degree of metabolic control. In addition, we aimed to evaluate this particle as a biomarker for HNF-1α MODY. RESEARCH DESIGN AND METHODS - We included 33 diabetic patients from the Polish Nationwide Registry of MODY. In addition, we examined 43 type 2 diabetic patients and 47 nondiabetic control subjects. The 1,5-AG concentration was measured with an enzymatic assay (GlycoMark). Receiver operating characteristic (ROC) curve analysis was used to evaluate 1,5-AG as a screening marker for HNF-1α MODY. RESULTS - The mean 1,5-AG plasma concentration in diabetic HNF-1α mutation carriers was 5.9 μg/ml, and it was lower than that in type 2 diabetic patients (11.0 μg/ml, P = 0.003) and in nondiabetic control subjects (23.9 μg/ml, P < 0.00005). The ROC curve analysis revealed 85.7% sensitivity and 80.0% specificity of 1,5-AG in screening for HNF-1α MODY at the criterion of <6.5 μg/ml in patients with an A1C level between 6.5 and 9.0%. CONCLUSIONS - 1,5-AG may be a useful biomarker for differential diagnosis of patients with HNF-1α MODY with a specific range of A1C, although this requires further investigation. However, the clinical use of this particle in diabetic HNF-1α mutation carriers for metabolic control has substantial limitations

Transcriptome Analysis of Proximal Tubular Cells (HK-2) Exposed to Urines of Type 1 Diabetes Patients at Risk of Early Progressive Renal Function Decline

Background: In patients with Type 1 Diabetes (T1D) who develop microalbuminuria, progressive decline in glomerular filtration rate (GFR) may be initiated by leakage into the urine of toxic proteins (txUPs). This study tested this hypothesis. Methods: After archiving baseline urine, we followed T1D patients with microalbuminuria for 8–12 years to distinguish those in whom GFR declined (Decliners) and those in whom it remained stable (Non-decliners). Human proximal tubular cells (HK-2 cells) were grown in serum-free medium enriched with pooled urines from Decliners or Non-decliners. We determined genome-wide expression profiles in extracted mRNA. Results: The two pooled urines induced differential expression of 312 genes. In terms of gene ontology, molecular functions of the 119 up-regulated genes were enriched for protein binding and peptidase inhibitor activities. Their biologic processes were enriched for defense response, responses to other organisms, regulation of cellular processes, or response to stress or stimulus, and programmed cell death. The 195 down-regulated genes were disproportionately represented in molecular functions of cation binding, hydrolase activity, and DNA binding. They were disproportionately represented in biological processes for regulation of metabolic processes, nucleic acid metabolic processes, cellular response to stress and macromolecule biosynthesis. The set of up-regulated genes in HK-2 cells overlaps significantly with sets of over-expressed genes in tubular and interstitial compartments of kidney biopsies from patients with advanced DN (33 genes in one study and 25 in the other compared with 10.3 expected by chance, p<$10^{−9}$ and p<$10^{−4}$, respectively). The overlap included genes encoding chemokines and cytokines. Overlap of down-regulated genes was no more than expected by chance. Conclusions: Molecular processes in tubules and interstitium seen in advanced diabetic nephropathy can be induced in vitro by exposure to urine from patients with minimal microalbuminuria who subsequently developed progressive renal function decline, presumably due to putative txUPs

The role of insulin resistance candidate gene polymorphisms in susceptibility to type 2 diabetes mellitus in a Polish population

WSTĘP. W cukrzycy typu 2 współistnieją upośledzenie wydzielania insuliny i zmniejszona wrażliwość na jej działanie. Celem badania było poszukiwanie związku polimorfizmów w genach kandydatach insulinooporności (–308 GÆA w promotorze genu TNF-a (tumor necrosis factor a) oraz wariantu aminokwasowego K121Q w genie PC-1) z cukrzycą typu 2 w populacji polskiej oraz przeanalizowanie wpływu powyższych polimorfizmów na przedcukrzycowe cechy ilościowe. MATERIAŁ I METODY. Przebadano 732 osoby. Do analizy związku wybranych markerów z cukrzycą typu 2 włączono 612 niespokrewnionych osób (case-control analysis): 358 chorych na cukrzycę i 254 osoby z grupy kontrolnej. W analizie przedcukrzycowych cech ilościowych przebadano 120 osób z prawidłowymi stężeniami glukozy (średni wiek: 34,2 roku, średni BMI: 27,9), z dodatnim wywiadem rodzinnym w kierunku cukrzycy typu 2. W grupie tej dokonano pomiaru stężeń insuliny i glukozy podczas doustnego testu tolerancji glukozy (OGTT, oral glucose tolerance test) oraz obliczono pośrednie wskaźniki wrażliwości na insulinę. U wszystkich badanych osób przeprowadzono genotypowanie metodą zmiennej długości fragmentów restrykcyjnych (RFLP, restriction fragment length polymorphism). W analizie statystycznej w badaniu osób niespokrewnionych użyto testu c2. W części projektu, związanej z cechami ilościowymi, zastosowano wieloczynnikową analizę wariancji (ANOVA) z uwzględnieniem wpływu płci, wieku i wskaźnika masy ciała (BMI, body mass index). WYNIKI. Stwierdzono zbliżony rozkład alleli u chorych na cukrzycę typu 2 i u osób z grupy kontrolnej: 15,7%/84,2% vs. 14,0%/86,0%, p = 0,38 dla polimorfizmu –308 GÆA TNF-a i 12,9%/87,1% vs. 13,1%/ /86,9%, p = 0,86 dla wariantu aminokwasowego K121Q genu PC-1. Podobnie nie zaobserwowano różnic w rozkładzie genotypów. Jednak przy analizie cech ilościowych nosiciele przynajmniej jednego allelu A w genie TNF-a (28% analizowanych osób) cechowali się wyższym wskaźnikiem obliczonym jako stosunek stężenia insuliny w 120. minucie do stężenia insuliny na czczo niż nosiciele genotypu GG (5,9 ± ± 6,5 vs. 3,4 ± 2,4; p = 0,04). Ponadto, pewne dodatkowe różnice wykazano w analizie stratyfikacyjnej, przeprowadzonej na podstawie BMI, płci i wieku chorych w odniesieniu do obu badanych polimorfizmów. WNIOSKI. Oba badane markery, –308 GÆA promotora genu TNF-a oraz wariant aminokwasowy K121Q PC-1, wydają się wpływać na przedcukrzycowe cechy ilościowe w populacji polskiej. Nie znaleziono natomiast dowodów ich związku z cukrzycą typu 2 w badanej populacji.INTRODUCTION. Insulin secretion impairment and decreased insulin sensitivity coexist in type 2 diabetes mellitus. Aim of the study was: 1) to search for the association of insulin resistance candidate gene markers, the TNF-a –308 G/A promoter polymorphism and the K121Q PC-1 variant, with type 2 diabetes in a Polish population; 2) to examine their influence on pre-diabetes quantitative traits. MATERIALS AND METHODS. Overall 732 subjects were examined. For case-control analysis we included 612 individuals: 358 type 2 diabetes patients and 254 controls. To assess prediabetic quantitative traits we examined 120 normoglycaemic individuals (the mean age: 34.2 years, the mean BMI: 27.9) with a family history of type 2 diabetes. The insulin and glucose levels were measured during OGTT and secondary indices were calculated. The groups were genotyped using RFLP. For the case-control study c2 test was used. For quantitative traits a multivariate linear regression analysis was employed. RESULTS. The allele distribution was similar in the group of patients and in the controls: (15.7%/84.2% vs. 14.0%/86.0%, p = 0.38, for the - 308 G/A TNF-a polymorphism, and 12.9%/87.1% vs. 13.1%/86.9%, p = 0.86, for K121Q PC-1 variant, respectively). Similarly, there was no difference in the genotype distribution. However, the carriers of at least one TNF1-a A allele (28% of the analyzed subjects) showed a higher ratio of 120-min insulin to the fasting insulin versus GG carriers (5.9 ± 6.5 vs. 3.4 ± 2.4; p = 0.04). Moreover, some additional differences were found for both markers in stratified analyses based on BMI, gender and age at examination. CONCLUSION. Both examined markers, the TNF-a -308 GÆA promoter polymorphism and the K121Q PC-1 variant, seem to influence the prediabetic quantitative traits in a Polish population. However, in case-control study we did not find the evidence of their association with type 2 diabetes in a Polish population

The role of some clinical risk factors on the pathogenesis of diabetic retinopathy in type 2 diabetic patients from a Polish population

WSTĘP. Retinopatia cukrzycowa jest najczęstszym przewlekłym powikłaniem mikronaczyniowym cukrzycy. W przypadku znacznego zaawansowania zmian prowadzi do zaburzeń widzenia, a nawet do utraty wzroku. Celami niniejszej pracy były ocena w badaniu przekrojowym częstości występowania retinopatii cukrzycowej u chorych na cukrzycę typu 2 w populacji polskiej oraz analiza związku wybranych cech klinicznych z retinopatią. MATERIAŁ I METODY. Badaniem objęto chorych na cukrzycę typu 2 leczonych w Poradni Diabetologicznej Katedry i Kliniki Chorób Metabolicznych CM UJ w Krakowie. Pacjenci wypełniali kwestionariusz dotyczący wywiadu chorobowego, chorób współtowarzyszących, leczenia, nałogów, wywiadu rodzinnego w kierunku cukrzycy. Wykonano badania biochemiczne, badanie okulistyczne, w tym badanie oftalmoskopowe dna oka po poszerzeniu źrenicy oraz fotografie dna oka. WYNIKI. W badaniu uczestniczyło 359 chorych na cukrzycę typu 2 - 198 kobiet (55,2%) i 161 mężczyzn (44,8%), w średnim wieku 60,8 ± 9,4 roku, BMI 31,3 ± 7,4 kg/m2, czasem trwania choroby 11,2 ± ± 7,0 lat oraz HbA1c 7,5 ± 1,5%. Retinopatię cukrzycową stwierdzono u 33,7% badanych. W przypadku, gdy choroba trwa do 10 lat, retinopatię wykazano u 18,3% pacjentów (n = 33), w okresie 10–20 lat - u 43,7% (n = 52), a jeśli cukrzyca trwała dłużej niż 20 lat - u 62,5% badanych (n = 35). W analizie wieloczynnikowej niezależnymi czynnikami ryzyka retinopatii okazały się: wiek rozpoznania cukrzycy (p = 0,01; OR: 0,96; 95% CI: 0,92–0,99), czas trwania choroby (p = 0,003; OR: 1,06; 95% CI: 1,02–1,10), HbA1c (p = 0,001; OR: 1,35; 95% CI: 1,13–1,63), niepalenie tytoniu (p = 0,001; OR: 0,41; 95% CI: 0,23– -0,71) oraz stężenie mocznika (p = 0,009; OR: 1,19; 95% CI: 1,05–1,36). WNIOSKI. W badanej grupie wykazano dużą częstość retinopatii cukrzycowej (33,7%). Chorobowość zwiększała się wraz z czasem trwania schorzenia. Niezależnymi czynnikami ryzyka retinopatii były: wiek zachorowania, czas trwania choroby, stężenia HbA1c i mocznika oraz niepalenie tytoniu.BACKGROUND. Type 2 diabetes mellitus (T2DM) is a complex, multifactorial disease that is a consequence of the progressive insulin secretory defect and peripheral insulin resistance. In the course of disease the long-lasting hyperglycaemia leads to the chronic complications. Diabetic retinopathy is a highly specific microvascular complication of this disease. It is the most frequent cause of new cases of blindness among adults. The aim of the study was to define the prevalence of diabetic retinopathy in patients with T2DM from a Polish population and to analyze the clinical features associated with this complication in the examined group. MATERIAL AND METHODS. The study group consisted of 359 T2DM patients with age of diagnosis above 35 years. The diagnosis of DR was based on the ophthalmologic examination and ophthalmoscopy after the dilation of pupils. The photographic documentation was done. Potentially important clinical covariables such as gender, age, duration of diabetes, BMI, smoking status, the presence of hypertension and some biochemical factors were also measured. RESULTS. We examined 359 subjects, all European Caucasians, residents of Poland with T2DM. The examined group consisted of 198 (55.2%) female and 161 (44.8%) male T2DM patients (mean age at examination: 60.8 ± 9.4 years, age at T2DM diagnosis: 49.7 ± 9.2, T2DM duration: 11.2 ± 7.0 years, body mass index: 31.3 ± 7.4 kg/m2, HbA1c: 7.5 ± 1.5 %). Diabetic retinopathy of different stages was detected in one third of the examined diabetic group (33.7%). Proliferative retinopathy was diagnosed in 8 subjects, what constituted 2.2% of the entire T2DM group. The morbidity differed in the sub-groups defined based on the disease duration. Among the patients with diabetes duration below 10 years retinopathy was diagnosed in 18.3% (n = 33) patients, while in the sub-group with diabetes duration between 10 and 20 years retinopathy was present in 43.7% (n = 52) of T2DM individuals. In the group of patients with the longest history of diabetes (above 20 years), retinopathy was observed in 62.5% (n = 35) subjects. The multivariate analysis revealed that significant predictors of diabetic retinopathy were: age at diagnosis of diabetes (p = 0.01; OR: 0.96; 95% CI: 0.92–0.99), duration of diabetes (p = 0.003; OR: 1.06; 95% CI: 1.02-1.10), HbA1c level (p = 0.001; OR: 1.35; 95% CI 1.13–1.63), never-smoking status (p = 0.001; OR: 0.41; 95% CI 0.23–0.71), and urea serum level (p = 0.009; OR 1.19; 95% CI: 1.05–1.36). CONCLUSIONS. The prevalence of diabetic retinopathy was 33.7% in examined populations. We were able to confirm the role of some clinical risk factors in the pathogenesis of DR such as age at diagnosis of diabetes, duration of the disease, HbA1c level, never-smoking status, urea serum level

The role of some clinical risk factors on the pathogenesis of diabetc retinopathy in type 2 diabetic patients from a Polish population

WSTĘP. Retinopatia cukrzycowa jest najczęstszym przewlekłym powikłaniem mikronaczyniowym cukrzycy. W przypadku znacznego zaawansowania zmian prowadzi do zaburzeń widzenia, a nawet do utraty wzroku. Celami niniejszej pracy były ocena w badaniu przekrojowym częstości występowania retinopatii cukrzycowej u chorych na cukrzycę typu 2 w populacji polskiej oraz analiza związku wybranych cech klinicznych z retinopatią. MATERIAŁ I METODY. Badaniem objęto chorych na cukrzycę typu 2 leczonych w Poradni Diabetologicznej Katedry i Kliniki Chorób Metabolicznych CM UJ w Krakowie. Pacjenci wypełniali kwestionariusz dotyczący wywiadu chorobowego, chorób współtowarzyszących, leczenia, nałogów, wywiadu rodzinnego w kierunku cukrzycy. Wykonano badania biochemiczne, badanie okulistyczne, w tym badanie oftalmoskopowe dna oka po poszerzeniu źrenicy oraz fotografie dna oka. WYNIKI. W badaniu uczestniczyło 359 chorych na cukrzycę typu 2 - 198 kobiet (55,2%) i 161 mężczyzn (44,8%), w średnim wieku 60,8 &#177; 9,4 roku, BMI 31,3 &#177; 7,4 kg/m2, czasem trwania choroby 11,2 &#177; 7,0 lat oraz HbA1c 7,5 &#177; 1,5%. Retinopatię cukrzycową stwierdzono u 33,7% badanych. W przypadku, gdy choroba trwa do 10 lat, retinopatię wykazano u 18,3% pacjentów (n = 33), w okresie 10-20 lat - u 43,7% (n = 52), a jeśli cukrzyca trwała dłużej niż 20 lat - u 62,5% badanych (n = 35). W analizie wieloczynnikowej niezależnymi czynnikami ryzyka retinopatii okazały się: wiek rozpoznania cukrzycy (p = 0,01; OR: 0,96; 95% CI: 0,92-0,99), czas trwania choroby (p = 0,003; OR: 1,06; 95% CI: 1,02-1,10), HbA1c (p = 0,001; OR: 1,35; 95% CI: 1,13-1,63), niepalenie tytoniu (p = 0,001; OR: 0,41; 95% CI: 0,23-0,71) oraz stężenie mocznika (p = 0,009; OR: 1,19; 95% CI: 1,05-1,36). WNIOSKI. W badanej grupie wykazano dużą częstość retinopatii cukrzycowej (33,7%). Chorobowość zwiększała się wraz z czasem trwania schorzenia. Niezależnymi czynnikami ryzyka retinopatii były: wiek zachorowania, czas trwania choroby, stężenia HbA1c i mocznika oraz niepalenie tytoniu.BACKGROUND. Type 2 diabetes mellitus (T2DM) is a complex, multifactorial disease that is a consequence of the progressive insulin secretory defect and peripheral insulin resistance. In the course of disease the long-lasting hyperglycaemia leads to the chronic complications. Diabetic retinopathy is a highly specific microvascular complication of this disease. It is the most frequent cause of new cases of blindness among adults. The aim of the study was to define the prevalence of diabetic retinopathy in patients with T2DM from a Polish population and to analyze the clinical features associated with this complication in the examined group. MATERIAL AND METHODS. The study group consisted of 359 T2DM patients with age of diagnosis above 35 years. The diagnosis of DR was based on the ophthalmologic examination and ophthalmoscopy after the dilation of pupils. The photographic documentation was done. Potentially important clinical covariables such as gender, age, duration of diabetes, BMI, smoking status, the presence of hypertension and some biochemical factors were also measured. RESULTS. We examined 359 subjects, all European Caucasians, residents of Poland with T2DM. The examined group consisted of 198 (55.2%) female and 161 (44.8%) male T2DM patients (mean age at examination: 60.8 &#177; 9.4 years, age at T2DM diagnosis: 49.7 &#177; 9.2, T2DM duration: 11.2 &#177; 7.0 years, body mass index: 31.3 &#177; 7.4 kg/m2, HbA1c: 7.5 &#177; 1.5 %). Diabetic retinopathy of different stages was detected in one third of the examined diabetic group (33.7%). Proliferative retinopathy was diagnosed in 8 subjects, what constituted 2.2% of the entire T2DM group. The morbidity differed in the sub-groups defined based on the disease duration. Among the patients with diabetes duration below 10 years retinopathy was diagnosed in 18.3% (n = 33) patients, while in the sub-group with diabetes duration between 10 and 20 years retinopathy was present in 43.7% (n = 52) of T2DM individuals. In the group of patients with the longest history of diabetes (above 20 years), retinopathy was observed in 62.5% (n = 35) subjects. The multivariate analysis revealed that significant predictors of diabetic retinopathy were: age at diagnosis of diabetes (p = 0.01; OR: 0.96; 95% CI: 0.92-0.99), duration of diabetes (p = 0.003; OR: 1.06; 95% CI: 1.02-1.10), HbA1c level (p = 0.001; OR: 1.35; 95% CI 1.13-1.63), never-smoking status (p = 0.001; OR: 0.41; 95% CI 0.23-0.71), and urea serum level (p = 0.009; OR 1.19; 95% CI: 1.05-1.36). CONCLUSIONS. The prevalence of diabetic retinopathy was 33.7% in examined populations. We were able to confirm the role of some clinical risk factors in the pathogenesis of DR such as age at diagnosis of diabetes, duration of the disease, HbA1c level, never smoking status, urea serum level

Genome-Wide Association Scan for Diabetic Nephropathy Susceptibility Genes in Type 1 Diabetes

OBJECTIVE—Despite extensive evidence for genetic susceptibility to diabetic nephropathy, the identification of susceptibility genes and their variants has had limited success. To search for genes that contribute to diabetic nephropathy, a genome-wide association scan was implemented on the Genetics of Kidneys in Diabetes collection. RESEARCH DESIGN AND METHODS—We genotyped 360,000 single nucleotide polymorphisms (SNPs) in 820 case subjects (284 with proteinuria and 536 with end-stage renal disease) and 885 control subjects with type 1 diabetes. Confirmation of implicated SNPs was sought in 1,304 participants of the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) study, a long-term, prospective investigation of the development of diabetes- associated complications. RESULTS—A total of 13 SNPs located in four genomic loci were associated with diabetic nephropathy with P1105. The strongest association was at the FRMD3 (4.1 protein ezrin, radixin, moesin [FERM] domain containing 3) locus (odds ratio [OR]1.45, P5.0107). A strong association was also identified at the CARS (cysteinyl-tRNA synthetase) locus (OR 1.36, P3.1106). Associations between both loci and time to onset of diabetic nephropathy were supported in the DCCT/EDIC study (hazard ratio [HR]1.33, P0.02, and HR1.32, P 0.01, respectively). We demonstrated expression of both FRMD3 and CARS in human kidney. CONCLUSIONS—We identified genetic associations for susceptibility to diabetic nephropathy at two novel candidate loci near the FRMD3 and CARS genes. Their identification implicates previously unsuspected pathways in the pathogenesis of this important late complication of type 1 diabetes

Gas Exchanges in the Leaves of Silage Maize Depending on the Forecrop and Maize Development Stage

Crop rotation is an important factor limiting maize productivity in a sustainable farming system. A field trial was conducted to investigate: (i) whether the cultivation of silage maize in a short (2-year) crop rotation in succession after a grassland (grassland-maize), winter triticale (winter triticale-maize), or after maize (maize-maize) will affect the course of the photosynthetic process; (ii) whether these processes will be determined by the stage of maize development; and (iii) whether there is a relationship between gas exchange parameters, foliage characteristics, and silage maize yield. The study was carried out in the years 2017–2018 at the stages (BBCH): stem elongation (36) and flowering (65). Gas exchange parameters, features of foliage development, and the maize yield were evaluated. It was demonstrated that photosynthesis of maize grown after grassland was more efficient than after triticale and maize (higher stomatal conductance, transpiration rate, intercellular CO2 concentration, and lower temperature). This result obtained by growing maize after grassland resulted in more favourable foliage characteristics (leaf area, leaf area index, chlorophyll content) and translated into a higher yield volume than after triticale and maize. The obtained results confirmed the positive role of grassland as a forecrop for maize compared to growing maize after winter triticale and after maize

The Effects of Soil Compaction and Different Tillage Systems on the Bulk Density and Moisture Content of Soil and the Yields of Winter Oilseed Rape and Cereals

Progressive soil compaction is a disadvantage of intensive tillage. Compaction exerts a negative impact on the physical properties of soil and decreases crop performance. The adverse effects of soil compaction can be mitigated by replacing conventional tillage with simplified tillage techniques. Simplified tillage exerts a protective effect on soil, reduces production costs and preserves agricultural ecosystems. The aim of this study was to determine the influence of compaction and different tillage methods on the bulk density and moisture content of soil. The experimental factors were as follows: Soil compaction before sowing (non-compacted control treatment and experimental treatments where soil was compacted after the harvest of the preceding crop) and four different methods of seedbed preparation in a three-field rotation system (winter oilseed rape, winter wheat, spring barley). The influence of compaction on the bulk density and moisture content of soil varied across the rotated crops and their developmental stages. Soil compaction had no significant effect on the analyzed parameters in the cultivation of winter oilseed rape. In treatments sown with winter wheat, soil compaction resulted in significantly lower soil density and significantly higher soil moisture content. In plots sown with spring barley, soil compaction led to a significant increase in the values of both parameters. The average bulk density of soil after various tillage operations in the examined crop rotation system ranged from 1.49–1.69 g·m−3 (winter oilseed rape), 1.47–1.59 g·m−3 (winter wheat), 1.47–1.61 g·m−3 (spring barley). The bulk density and moisture content of soil were lowest after conventional tillage (control treatment) and higher after simplified tillage. Regardless of soil compaction, the greatest reduction in winter oilseed rape yields was noted in response to skimming, harrowing and the absence of pre-sowing plowing. Spring barley yields were higher in non-compacted treatments, whereas the reverse was observed in winter wheat. Chisel plowing and single plowing induced the greatest decrease in wheat yields relative to conventional tillage. Single plowing significantly decreased the grain yield of spring barley relative to the tillage system that involved skimming and fall plowing to a depth of 25