diff --git a/models/issue.go b/models/issue.go
index 2345e6f672de..3fcdab6164c6 100644
--- a/models/issue.go
+++ b/models/issue.go
@@ -95,8 +95,8 @@ func (issue *Issue) IsOverdue() bool {
 }
 
 // LoadRepo loads issue's repository
-func (issue *Issue) LoadRepo(ctx DBContext) error {
-	return issue.loadRepo(ctx.e)
+func (issue *Issue) LoadRepo() error {
+	return issue.loadRepo(x)
 }
 
 func (issue *Issue) loadRepo(e Engine) (err error) {
@@ -714,11 +714,6 @@ func updateIssueCols(e Engine, issue *Issue, cols ...string) error {
 	return nil
 }
 
-// UpdateIssueCols only updates values of specific columns for given issue.
-func UpdateIssueCols(ctx DBContext, issue *Issue, cols ...string) error {
-	return updateIssueCols(ctx.e, issue, cols...)
-}
-
 func (issue *Issue) changeStatus(e *xorm.Session, doer *User, isClosed bool) (err error) {
 	// Reload the issue
 	currentIssue, err := getIssueByID(e, issue.ID)
@@ -843,6 +838,38 @@ func (issue *Issue) ChangeStatus(doer *User, isClosed bool) (err error) {
 	return nil
 }
 
+// ChangeTitle changes the title of this issue, as the given user.
+func (issue *Issue) ChangeTitle(doer *User, oldTitle string) (err error) {
+	sess := x.NewSession()
+	defer sess.Close()
+
+	if err = sess.Begin(); err != nil {
+		return err
+	}
+
+	if err = updateIssueCols(sess, issue, "name"); err != nil {
+		return fmt.Errorf("updateIssueCols: %v", err)
+	}
+
+	if err = issue.loadRepo(sess); err != nil {
+		return fmt.Errorf("loadRepo: %v", err)
+	}
+
+	if _, err = createChangeTitleComment(sess, doer, issue.Repo, issue, oldTitle, issue.Title); err != nil {
+		return fmt.Errorf("CreateChangeTitleComment: %v", err)
+	}
+
+	if err = issue.neuterCrossReferences(sess); err != nil {
+		return err
+	}
+
+	if err = issue.addCrossReferences(sess, doer); err != nil {
+		return err
+	}
+
+	return sess.Commit()
+}
+
 // AddDeletePRBranchComment adds delete branch comment for pull request issue
 func AddDeletePRBranchComment(doer *User, repo *Repository, issueID int64, branchName string) error {
 	issue, err := getIssueByID(x, issueID)
diff --git a/models/issue_comment.go b/models/issue_comment.go
index 8e2fa43f86c1..e8043c1ec7f3 100644
--- a/models/issue_comment.go
+++ b/models/issue_comment.go
@@ -468,7 +468,7 @@ func (c *Comment) CodeCommentURL() string {
 	return fmt.Sprintf("%s/files#%s", c.Issue.HTMLURL(), c.HashTag())
 }
 
-func createComment(e Engine, opts *CreateCommentOptions) (_ *Comment, err error) {
+func createComment(e *xorm.Session, opts *CreateCommentOptions) (_ *Comment, err error) {
 	var LabelID int64
 	if opts.Label != nil {
 		LabelID = opts.Label.ID
@@ -519,7 +519,7 @@ func createComment(e Engine, opts *CreateCommentOptions) (_ *Comment, err error)
 	return comment, nil
 }
 
-func sendCreateCommentAction(e Engine, opts *CreateCommentOptions, comment *Comment) (err error) {
+func sendCreateCommentAction(e *xorm.Session, opts *CreateCommentOptions, comment *Comment) (err error) {
 	// Compose comment action, could be plain comment, close or reopen issue/pull request.
 	// This object will be used to notify watchers in the end of function.
 	act := &Action{
@@ -690,9 +690,8 @@ func createDeadlineComment(e *xorm.Session, doer *User, issue *Issue, newDeadlin
 	})
 }
 
-// CreateChangeTitleComment created a change title comment for issue
-func CreateChangeTitleComment(ctx DBContext, doer *User, repo *Repository, issue *Issue, oldTitle, newTitle string) (*Comment, error) {
-	return createComment(ctx.e, &CreateCommentOptions{
+func createChangeTitleComment(e *xorm.Session, doer *User, repo *Repository, issue *Issue, oldTitle, newTitle string) (*Comment, error) {
+	return createComment(e, &CreateCommentOptions{
 		Type:     CommentTypeChangeTitle,
 		Doer:     doer,
 		Repo:     repo,
diff --git a/models/issue_lock.go b/models/issue_lock.go
index b927bab093c1..dc6655ad3b51 100644
--- a/models/issue_lock.go
+++ b/models/issue_lock.go
@@ -28,7 +28,6 @@ func updateIssueLock(opts *IssueLockOptions, lock bool) error {
 	}
 
 	opts.Issue.IsLocked = lock
-
 	var commentType CommentType
 	if opts.Issue.IsLocked {
 		commentType = CommentTypeLock
@@ -36,16 +35,26 @@ func updateIssueLock(opts *IssueLockOptions, lock bool) error {
 		commentType = CommentTypeUnlock
 	}
 
-	if err := UpdateIssueCols(DefaultDBContext(), opts.Issue, "is_locked"); err != nil {
+	sess := x.NewSession()
+	defer sess.Close()
+	if err := sess.Begin(); err != nil {
+		return err
+	}
+
+	if err := updateIssueCols(sess, opts.Issue, "is_locked"); err != nil {
 		return err
 	}
 
-	_, err := CreateComment(&CreateCommentOptions{
+	_, err := createComment(sess, &CreateCommentOptions{
 		Doer:    opts.Doer,
 		Issue:   opts.Issue,
 		Repo:    opts.Issue.Repo,
 		Type:    commentType,
 		Content: opts.Reason,
 	})
-	return err
+	if err != nil {
+		return err
+	}
+
+	return sess.Commit()
 }
diff --git a/models/issue_test.go b/models/issue_test.go
index fe5af5c190a8..0be3f6880825 100644
--- a/models/issue_test.go
+++ b/models/issue_test.go
@@ -160,7 +160,7 @@ func TestUpdateIssueCols(t *testing.T) {
 	issue.Content = "This should have no effect"
 
 	now := time.Now().Unix()
-	assert.NoError(t, UpdateIssueCols(DefaultDBContext(), issue, "name"))
+	assert.NoError(t, updateIssueCols(x, issue, "name"))
 	then := time.Now().Unix()
 
 	updatedIssue := AssertExistsAndLoadBean(t, &Issue{ID: issue.ID}).(*Issue)
diff --git a/models/issue_xref.go b/models/issue_xref.go
index 3f02741bef3d..1cc0bcfe6a11 100644
--- a/models/issue_xref.go
+++ b/models/issue_xref.go
@@ -10,6 +10,7 @@ import (
 
 	"code.gitea.io/gitea/modules/log"
 
+	"github.com/go-xorm/xorm"
 	"github.com/unknwon/com"
 )
 
@@ -50,7 +51,7 @@ type crossReferencesContext struct {
 	OrigComment *Comment
 }
 
-func newCrossReference(e Engine, ctx *crossReferencesContext, xref *crossReference) error {
+func newCrossReference(e *xorm.Session, ctx *crossReferencesContext, xref *crossReference) error {
 	var refCommentID int64
 	if ctx.OrigComment != nil {
 		refCommentID = ctx.OrigComment.ID
@@ -97,12 +98,7 @@ func neuterCrossReferences(e Engine, issueID int64, commentID int64) error {
 //          \/     \/            \/
 //
 
-// AddCrossReferences adds issues cross references
-func (issue *Issue) AddCrossReferences(ctx DBContext, doer *User) error {
-	return issue.addCrossReferences(ctx.e, doer)
-}
-
-func (issue *Issue) addCrossReferences(e Engine, doer *User) error {
+func (issue *Issue) addCrossReferences(e *xorm.Session, doer *User) error {
 	var commentType CommentType
 	if issue.IsPull {
 		commentType = CommentTypePullRef
@@ -117,7 +113,7 @@ func (issue *Issue) addCrossReferences(e Engine, doer *User) error {
 	return issue.createCrossReferences(e, ctx, issue.Title+"\n"+issue.Content)
 }
 
-func (issue *Issue) createCrossReferences(e Engine, ctx *crossReferencesContext, content string) error {
+func (issue *Issue) createCrossReferences(e *xorm.Session, ctx *crossReferencesContext, content string) error {
 	xreflist, err := ctx.OrigIssue.getCrossReferences(e, ctx, content)
 	if err != nil {
 		return err
@@ -130,7 +126,7 @@ func (issue *Issue) createCrossReferences(e Engine, ctx *crossReferencesContext,
 	return nil
 }
 
-func (issue *Issue) getCrossReferences(e Engine, ctx *crossReferencesContext, content string) ([]*crossReference, error) {
+func (issue *Issue) getCrossReferences(e *xorm.Session, ctx *crossReferencesContext, content string) ([]*crossReference, error) {
 	xreflist := make([]*crossReference, 0, 5)
 	var xref *crossReference
 
@@ -216,11 +212,6 @@ func (issue *Issue) isValidCommentReference(e Engine, ctx *crossReferencesContex
 	}, nil
 }
 
-// NeuterCrossReferences updated issues' cross references
-func (issue *Issue) NeuterCrossReferences(ctx DBContext) error {
-	return issue.neuterCrossReferences(ctx.e)
-}
-
 func (issue *Issue) neuterCrossReferences(e Engine) error {
 	return neuterCrossReferences(e, issue.ID, 0)
 }
@@ -233,7 +224,7 @@ func (issue *Issue) neuterCrossReferences(e Engine) error {
 //         \/             \/      \/     \/     \/
 //
 
-func (comment *Comment) addCrossReferences(e Engine, doer *User) error {
+func (comment *Comment) addCrossReferences(e *xorm.Session, doer *User) error {
 	if comment.Type != CommentTypeCode && comment.Type != CommentTypeComment {
 		return nil
 	}
diff --git a/routers/repo/issue.go b/routers/repo/issue.go
index bb11bb4719ea..16a049c7aa6d 100644
--- a/routers/repo/issue.go
+++ b/routers/repo/issue.go
@@ -757,7 +757,7 @@ func ViewIssue(ctx *context.Context) {
 						ctx.ServerError("GetIssueByID", err)
 						return
 					}
-					if err = otherIssue.LoadRepo(models.DefaultDBContext()); err != nil {
+					if err = otherIssue.LoadRepo(); err != nil {
 						ctx.ServerError("LoadRepo", err)
 						return
 					}
diff --git a/services/issue/issue.go b/services/issue/issue.go
index 6efe616c3e2b..a28916a7f9b5 100644
--- a/services/issue/issue.go
+++ b/services/issue/issue.go
@@ -51,30 +51,7 @@ func ChangeTitle(issue *models.Issue, doer *models.User, title string) (err erro
 	oldTitle := issue.Title
 	issue.Title = title
 
-	err = models.WithTx(func(ctx models.DBContext) error {
-		if err = models.UpdateIssueCols(ctx, issue, "name"); err != nil {
-			return fmt.Errorf("updateIssueCols: %v", err)
-		}
-
-		if err = issue.LoadRepo(ctx); err != nil {
-			return fmt.Errorf("loadRepo: %v", err)
-		}
-
-		if _, err = models.CreateChangeTitleComment(ctx, doer, issue.Repo, issue, oldTitle, title); err != nil {
-			return fmt.Errorf("CreateChangeTitleComment: %v", err)
-		}
-
-		if err = issue.NeuterCrossReferences(ctx); err != nil {
-			return err
-		}
-
-		if err = issue.AddCrossReferences(ctx, doer); err != nil {
-			return err
-		}
-		return nil
-	})
-
-	if err != nil {
+	if err = issue.ChangeTitle(doer, oldTitle); err != nil {
 		return
 	}
 
diff --git a/services/mailer/mail.go b/services/mailer/mail.go
index cdb95e9c47fa..3f0a789dc4cd 100644
--- a/services/mailer/mail.go
+++ b/services/mailer/mail.go
@@ -170,7 +170,7 @@ func composeIssueCommentMessage(issue *models.Issue, doer *models.User, content
 	} else {
 		subject = mailSubject(issue)
 	}
-	err := issue.LoadRepo(models.DefaultDBContext())
+	err := issue.LoadRepo()
 	if err != nil {
 		log.Error("LoadRepo: %v", err)
 	}
diff --git a/services/mailer/mail_issue.go b/services/mailer/mail_issue.go
index bdbbddc12b0a..da0249d595da 100644
--- a/services/mailer/mail_issue.go
+++ b/services/mailer/mail_issue.go
@@ -88,7 +88,7 @@ func mailIssueCommentToParticipants(issue *models.Issue, doer *models.User, cont
 		names = append(names, participants[i].Name)
 	}
 
-	if err := issue.LoadRepo(models.DefaultDBContext()); err != nil {
+	if err := issue.LoadRepo(); err != nil {
 		return err
 	}